AFCRL bibliography for the third quarter of 1972

ICARUS 20, 72--120 (1973)

AFCRL Bibliography for the Third Quarter of 1972 Air Force Cambridge Research Laboratory, Laurence G. Hanscom Field, Bedford, Massachusetts R e c e i v e d April 16, 1973

Presented in this section is a bibliography on lunar and planetary subjectsfurnished by the Air Force Cambridge Research Laboratory and supplied and edited by John W. Salisbury. Contributors are Joel E. M. Adler, Jens P. Dybwad, Graham Hunt, Charles Lenhoff, Lloyd Logan, Douglas A. Long, J. W. Salisbury, Lawrence Tolendino, and Karl Zinnow. The categories included are as follows: Astrobiology, Comets, Meteorite Craters and Cratering Effects, Meteors and Meteorites, M o o n - General, Moon--Atmosphere, Moon--Figure and InternalStructure, Moon Surface Features, Moon Surface Layer, Moon--Temperature, Origin of the Solar System, Planets--General, Planets--Jupiter, Planets Mars, Planets--Neptune, Planets-Pluto, P l a n e t s Saturn, Planets--Uranus, Planets--Venus, and Te]ctites. ED. ASTROBIOLOGY

m e r r y a t b a n d s c e n t e r e d a t 1500, 2000, 2500, 3000, 3300, a n d 4200A, for V e n u s , Mars, J u p i t e r , a n d S a t u r n , a n d of p h o t o m e t r y a t t h e l a t t e r four b a n d s for U r a n u s a n d N e p t u n e .

MOLTON, P., AND PONNA3IPERUMA, C., 1972. S u r v i v a l of c o m m o n t e r r e s t r i a l m i c r o o r g a n i s m s u n d e r s i m u l a t e d J o v i a n c o n d i t i o n s . Nature 238, 217-218. See P l a n e t s - - J u p i t e r , SAGAN, C., 1972. I n t e r s t e l l a r organic c h e m istry. Nature 238, 77-80. C o m p l e x organic molecules t h a t are s t a b l e a g a i n s t r a d i a t i o n m a y p e r v a d e i n t e r s t e l l a r space, w i t h t h e i r d e g r a d a t i o n p r o d u c t s a source of t h o s e molecules o b s e r v e d . T h e c o n n e x i o n b e t w e e n biological a n d inters t e l l a r organic c h e m i s t r y is, h o w e v e r , analogical r a t h e r t h a n s u b s t a n t i v e , a n d t h e p r o s p e c t for i n t e r s t e l l a r biology is dim.

ERSHKOVICH, A.

COMETS CODE, A. D., AND SAVAGE, B. D., 1972. O r b i t i n g a s t r o n o m i c a l o b s e r v a t o r y : R e v i e w of scientific results. Science 177, 213-221. R e s u l t s of u l t r a v i o l e t o b s e r v a t i o n s of stars, comets, planets, interstellar dust, interstellar hydrogen, o b j e c t s w i t h u l t r a v i o l e t e m i s s i o n lines, N o v a S e r p e n t i s 1970, galaxies, a n d v a r i a b l e stars, obtained by the Wisconsin experiment package o n b o a r d OAO-2, are reviewed. O b s e r v a t i o n s of c o m e t s T a g o - S a t o - K o s a k a (1969g) a n d B e n n e t t (1969i) r e v e a l e d , a m o n g o t h e r t h i n g s , t h e e x t e n s i v e L y m a n - a l p h a h y d r o g e n halo p r e d i c t e d earlier. T h e s p e c t r o p h o t o m e t r i c m e a s u r e m e n t s provide data on the distribution and temporal v a r i a t i o n s of OH, H , a n d O, a n d e s t a b l i s h a n u p p e r l i m i t to t h e H2 a b u n d a n c e . D a t a p e r t i n e n t t o p l a n e t a r y a t m o s p h e r e s consist of s p e c t r a l s c a n s o v e r t h e region 2000 to 3 0 0 0 A a n d p h o t o Copyright © 1973 by Academic Press, Inc. All rights of reproduction in any form reserved. Printed in Great Britain

I.,

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CHERN~:OV, A. A., 1972. Oscillations of t y p e - 1 c o m e t tails. Planet. Space Sci. 20, 1235-1243. W a v e m o t i o n s in type-1 c o m e t tails are s t u d i e d . A c o m e t tail is c o n s i d e r e d as a p l a s m a c y l i n d e r (with free b o u n d a r y - t a n g e n t i a l d i s c o n t i n u i t y surface) i m m e r s e d in t h e i n t e r p l a n e t a r y p l a s m a . I t is s h o w n t h a t q u a s i p e r i o d i c a l v a r i a t i o n s of type-1 c o m e t tail d i r e c t i o n w i t h a p e r i o d of some days, first d e s c r i b e d b y Bessel in 1836, m a y b e t h e eigenmodes, e x c i t e d b y solar w i n d parameter fluctuations. The authors have o b t a i n e d b o t h t h e c r i t e r i o n of K e l v i n - H c l m h o l t z i n s t a b i l i t y a n d t h e g r o w t h r a t e of h y d r o m a g n e t i c waves. A n u m b e r of o b s e r v e d effects are interp r e t e d as a r e s u l t of K e l v i n - H e l m h o l t z ins t a b i l i t y , for i n s t a n c e , t h e helical w a v e s in t h e c o m e t tails a n d t h e increase of w a v e a m p l i t u d e w h e n m o v i n g f r o m M o r e h o u s e c o m a to its tail. MYER, J . A., 1972. D i r e c t i n f r a r e d m e a s u r e m e n t s of t h e r m a l r a d i a t i o n f r o m t h e n u c l e u s of C o m e t B e n n e t t . Ap. J. 175, L 4 9 - L 5 3 . A t e c h n i q u e of c o n t r a s t r a d i o m e t r y e n a b l e d d i r e c t i n f r a r e d m e a s u r e m e n t s on t h e n u c l e u s of C o m e t 1969i. T h e i n t e n s i t y level of t h e o b s e r v a t i o n of 9.0 × 1 0 - 1 S w a t t s c m - 2 / ~ -1 is c o n s i s t e n t w i t h t h e m e a s u r e m e n t s of two o t h e r g r o u p s of observers. A s m a l l b u t slightly h o t t e r n u c l e u s may explain the irregular thermal radiation c o n t i n u u m o b s e r v e d b y one of t h e groups. A r o u g h c a l c u l a t i o n of 4 2 e - t / 2 k m (where e is t h e a v e r a g e e m i s s i v i t y of t h e n u c l e u s surface) is 72

METEORITE CRATERS AND CRATERI~G EFFECTS

m a d e for t h e r a d i u s of t h e c o m e t n u c l e u s b a s e d o n a n e s t i m a t e of its color t e m p e r a t u r e a n d o n t h e a s s u m p t i o n t h a t i t is s p h e r i c a l in shape. ROEMER, E., 1972. C o m e t n o t e s . Mercury 1, No. 4, 16-18. T h e discoveries of t w o n e w comets, C o m e t B r a d f i e l d , 1972f, a n d C o m e t Gehrels, 1972e, are described. T h e recoveries of P / G i a e o b i n i - Z i n n e r , 1972d, a n d P / N e u j m i n 3, 1972g, are r e p o r t e d . C o n t i n u i n g o b s e r v a t i o n s of P / T e m p e l 2, 1972c, P / T e m p e l 1, 1972a, P / G u n n , 1970p, P / W o l f - H a r r i n g t o n , 19700, a n d P / T s u c h i n s h a n 1 a n d 2 are r e l a t e d . ROEMER, E., 1972. C o m e t notes. Mercury 1, No. 5, 17-18. D i s c o v e r y of C o m e t S a n d a g e , 1972h, w h i c h is a n e w c o m e t of u n u s u a l l y large p e r i h e l i o n d i s t a n c e is described. C o n t i n u i n g o b s e r v a t i o n s of P / N e u j m i n 3, 1972g, Bradfield, 1972f, Gehrels, 1972e, P / G i a c o b i n i - Z i n n e r , 1972d, P / T e m p l e 2, 1972c, Grigg-Skjellerup, 1972b, P / T e m p l e 1, 1972a, a n d P / T s u c h i n s h a n 2, 1971d are r e p o r t e d . STIEF, L. J . , 1972. Origin of C a in comets. Nature 237, 29. T h e a u t h o r suggests t h a t a p o t e n t i a l source of Ca in c o m e t s is t h e p h o t o d i s s o c i a t i o n of p r o p y n e b y solar r a d i a t i o n , m o s t p r o b a b l y in t h e region of t h e s t r o n g 1 2 1 6 A Lyman-c¢ line. A l t h o u g h t h e overall process CsH4 -~ Cs + 2H2 is e n e r g e t i c a l l y possible b e l o w 1961 A, a m o r e e n e r g e t i c p h o t o n m a y b e r e q u i r e d if H 2 carries off some of t h e a v a i l a b l e energy. YABUSHITA, S., 1972. T h e d e p e n d e n c e o n i n c l i n a t i o n of t h e p l a n e t a r y p e r t u r b a t i o n s of t h e o r b i t s of l o n g - p e r i o d comets. Astron. Astrophys. 20, 205 214. P l a n e t a r y p e r t u r b a t i o n s of t h e o r b i t a l e l e m e n t s of l o n g - p e r i o d c o m e t s are c a l c u l a t e d o n t h e a s s u m p t i o n t h a t t h e o r b i t s are p a r a b o l a s . T h e p e r t u r b a t i o n of t h e b i n d i n g e n e r g y of H a l l e y ' s c o m e t c a l c u l a t e d b y t h e p a r a b o l i c a p p r o x i m a t i o n is c o m p a r e d w i t h Cowell a n d C r o m m e l i n ' s calculation. I t is s h o w n that the agreement between the two calculations is s u c h t h a t t h e p a r a b o l i c a p p r o x i m a t i o n c a n b e u s e d a t l e a s t q u a l i t a t i v e l y for c o m e t s w i t h periods as s h o r t as 77 years. T h e p a r a b o l i c a p p r o x i m a t i o n also gives t h e secular c h a n g e of t h e l o n g i t u d e of t h e a s c e n d i n g n o d e . I n accordance with Everhart's calculation, the perturbat i o n of t h e b i n d i n g e n e r g y is g r e a t e r for d i r e c t t h a n r e t r o g r a d e orbits. A p p l y i n g t h e L y t t l e t o n H a m m e r s l e y r a n d o m - w a l k t h e o r y of c o m e t a r y energy, d i r e c t c o m e t s are m o r e r a p i d l y expelled f r o m t h e solar s y s t e m t h a n r e t r o g r a d e ones. T h i s t h e o r e t i c a l d e d u c t i o n is c o m p a r e d w i t h t h e d i s t r i b u t i o n of i n c l i n a t i o n s of o b s e r v e d longp e r i o d comets. O n t h e t h e o r e t i c a l basis t h e r e s h o u l d b e a s m a l l e r n u m b e r of d i r e c t c o m e t s t h a n r e t r o g r a d e ones, w h i l e t h e o b s e r v a t i o n gives a l m o s t e q u a l n u m b e r s . T h e deficiency of

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o b s e r v e d c o m e t s n e a r i ( i n c l i n a t i o n ) ~ 130 ° excess m i g h t b e e x p l i c a b l e b y t h e w e a k n e s s of t h e p l a n e t a r y p e r t u r b a t i o n n e a r i ~ 120 °. METEORITE EFFECTS

CRATERS AND CRATERING

CRAWFORD, A. R., 1972. P o s s i b l e i m p a c t s t r u c t u r e i n I n d i a . Nature 237, 96. T h e S u r v e y shows a n i s o l a t e d hill of a n n u l a r shape, f o r m i n g a n a l m o s t c o m p l e t e circle a p p r o x i m a t e l y 3 k i n in e x t e r n a l d i a m e t e r . T h e f e a t u r e seems likely t o b e some k i n d of i m p a c t s t r u c t u r e . DAVIES, G. F., 1972. E q u a t i o n s of s t a t e a n d p h a s e e q u i l i b r i a of s t i s h o v i t e a n d a coesitelike phase from shock-wave and other data. J. Geophys. Res. 77, 4920-4933. S h o c k - w a v e , s t a t i c - c o m p r e s s i o n ( X ray), u l t r a s o n i c , t h e r m a l e x p a n s i o n , a n d t h e r m o d y n a m i c d a t a are simult a n e o u s l y i n v e r t e d to d e t e r m i n e t h e e q u a t i o n s of s t a t e of s t i s h o v i t e a n d a coesitelike SiO 2 p h a s e . All t h e s t i s h o v i t e d a t a e x c e p t t h e t h e r m a l e x p a n s i o n d a t a are satisfied b y a Mie-Griineisent y p e e q u a t i o n of s t a t e h a v i n g a zero p r e s s u r e b u l k m o d u l u s K of a b o u t 3.50 ± 0 . I M b , a p r e s s u r e d e r i v a t i v e dK/dP of 3.3 _+ 1, a n d a Griineisen p a r a m e t e r , i n i t i a l l y 1.25 ± 0.1, t h a t decreases slowly w i t h compression. T h e v o l u m e coefficient of t h e r m a l e x p a n s i o n a t a m b i e n t c o n d i t i o n s is f o u n d to be 13 i 1 × 10-6/°K, in c o m p a r i s o n w i t h 16.4 ± 1.3 m e a s u r e d b y W e a v e r . Some H u g o n i o t d a t a of T r u n i n et al. for v e r y p o r o u s q u a r t z h a v e d e n s i t i e s v e r y close to tile d e n s i t y of coesite. H o w e v e r , a c a l c u l a t i o n of t h e c o e s i t e - s t i s h o v i t e p h a s e line shows t h a t t h e coesitelike p h a s e persists to a b o u t t w i c e t h e p r e d i c t e d t r a n s i t i o n p r e s s u r e a t 10 000°K. I t is s u g g e s t e d t h a t t h e d i s c r e p a n c y c a n be e x p l a i n e d if t h i s p h a s e is i n t e r p r e t e d as a l i q u i d of a b o u t coesite d e n s i t y . DIETZ, R. S., AND McHO~E, J . F., 1972. Laguna Guatavita: Not meteoritic, probable salt collapse crater. Meteoritics 7, 303 307. L a g u n a G u a t a v i t a (Colombia), a c r a t e r 7 0 0 m across a n d 1 2 5 m deep c o n t a i n i n g a c e n t r a l lake, a p p e a r s n o t t o b e a m e t e o r i t e c r a t e r as w i d e l y s u p p o s e d . T h e t e c t o n i c style is n o t t h a t of a n i m p a c t site, a n d t h e r e is n o raised r i m or e j e c t e d debris. T h e a u t h o r s c o u l d find n o i m p a c t i t e , s h o c k m e t a m o r p h i c effects, or s h o c k f r a c t u r e s ( s h a t t e r cones). Most likely it is a collapsed c r a t e r c a u s e d b y t h e s o l u t i o n a n d w i t h d r a w a l of s a l t f r o m a n u n d e r l y i n g anticline. VEDDER, J . F., 1972. C r a t e r s f o r m e d in mineral dust by hypervelocity microparticles. J. Geophys. Res. 77, 4304-4309. As a s i m u l a t i o n of erosion processes o n t h e l u n a r surface, i m p a c t c r a t e r s were f o r m e d in d u s t t a r g e t s b y 2- t o

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AFCRL BIBLIOGRAPItY--nRD QUARTER 1972

5 - / z m - d i a m e t e r p o l y s t y r e n e s p h e r e s w i t h velocities b e t w e e n 2.5 a n d 12km/sec. F o r w e a k l y cohesive, t h i c k t a r g e t s o f basalt d u s t w i t h a m a x i m u m grain size c o m p a r a b l e to t h e projectile d i a m e t e r , t h e c r a t e r s h a d an a v e r a g e projectilet o - d i a m e t e r d i a m e t e r r a t i o of 25, a n d t h e disp l a c e d m a s s was 3 orders of m a g n i t u d e g r e a t e r t h a n t h e p r o j e c t i l e mass. The ratio o f t h e disp l a c e d m a s s to t h e kinetic e n e r g y o f t h e projectile was a b o u t 0.1keg//zJ. T h e s e ratios d e c r e a s e d as t h e cohesiveness o f t h e d u s t grains was increased. F o r grain sizes a n o r d e r o f m a g n i t u d e larger, t h e c r a t e r s were n o t well defined, b u t t h e ratios were a b o u t t h e same. No d e t e c t a b l e raised rim was p r o d u c e d b y e j e c t a or uplift o f t h e surface in a n y o f t h e s e eases. I n a s i m u l a t i o n o f t h e effect o f a d u s t c o v e r i n g on l u n a r rocks, a layer o f cohesive, fine-grained b a s a l t d u s t w i t h a t h i c k n e s s n e a r l y twice t h e p r o j e c t i l e d i a m e t e r p r o t e c t e d a glass s u b s t r a t e f r o m d a m a g e , b u t an area a b o u t 50 t i m e s t h e cross-sectionM area o f t h e projectile was cleared o f all b u t a few grains. I m p a c t d a m a g e was p r o d u c e d in glass u n d e r a t h i n n e r d u s t layer. The results are useful in s t u d i e s o f m i x i n g o f t h e fine f r a c t i o n o f t h e l u n a r regolith a n d shielding o f d u s t - c o a t e d l u n a r rock surfaces u n d e r b o m b a r d m e n t b y micromcteoroids. METEORS AND METEORITES BANDERMANN, L. W., 1972. E f f e c t s o f erosion a n d f r a g m e n t a t i o n on t h e m a s s d i s t r i b u t i o n o f colliding particles. ~1//. N . R. A. S. 160, 321-338. E f f e c t s o f erosion a n d f r a g m e n t a t i o n on t h e d i s t r i b u t i o n o f t h e masses o f an e n s e m b l e o f colliding particles are i n v e s t i g a t e d . A n e q u a t i o n for t h e i n s t a n t a n e o u s r a t e o f c h a n g e in t h e n u m b e r o f particles p e r u n i t m a s s r a n g e is f o r m u l a t e d a n d solved n u m e r i c a l l y . R e s u l t s for a v a r i e t y o f p h y s i c a l c o n d i t i o n s are p r e s e n t e d a n d c o m p a r e d w i t h results o b t a i n e d b y o t h e r authors. BEGE~XANN, F., 1972. A r g o n 37/Argon 39 a c t i v i t y ratios in m e t e o r i t e s a n d t h e spatial c o n s t a n c y o f t h e cosmic r a d i a t i o n . J. Geophys. Res. 77, 3650-3659. A r g o n 37 a n d a r g o n 39 h a v e b e e n m e a s u r e d in a b u l k s a m p l e a n d a m e t a l - r i c h f r a c t i o n o f t h e L o s t City s t o n e m e t e o r i t e . I n t h e b u l k s a m p l e t h e a c t i v i t y o f b o t h isotopes is in fair a g r e e m e n t w i t h t h e activities r e p o r t e d p r e v i o u s l y for t h i s m e t e o r i t e . The activities c a l c u l a t e d for t h e p u r e m e t a l p h a s e (3TAr = 15.1 ± 2 . 5 d p m / k g , agAr = 20.0 ± 1 . 5 d p m / k g ) , h o w e v e r , are different. I n p a r t i c u l a r , t h e a c t i v i t y r a t i o o f 0.75 4- 0.10 is c o n s i d e r a b l y h i g h e r t h a n t h e p r e v i o u s l y p u b l i s h e d values. C o n s e q u e n t l y t h e radial heliocentric g r a d i e n t o f t h e galactic

cosmic r a d i a t i o n is f o u n d to be m u c h smaller. The d a t a available for t h e a c t i v i t y ratios in t h e m e t a l o f different m e t e o r i t e s are discussed. B e c a u s e t h e wide s c a t t e r in t h e ratios o b s e r v e d in m e t e o r i t e s t h a t fell a t c o m p a r a b l e t i m e s d u r i n g t h e solar cycle is due to different d e c a y rates o f 37At, it is a r g u e d t h a t a t least d u r i n g solar m a x i m u m t h e ratios d e p e n d essentially on tile perihelions of t h e m e t e o r o i d orbits a n d on w h e t h e r t h e m e t e o r i t e s fall on e a r t h w h e n t h e y are on t h e i r i n w a r d - b o u n d t r i p or w h e n t h e y are going out. E x c e p t in special cases like L o s t City, different aphelions will h a v e a n o t i c e a b l e influence only for m e t e o r i t e s falling n e a r solar m i n i m u m , p r o v i d e d t h a t t h e spatial g r a d i e n t o f t h e c o s m i c - r a y i n t e n s i t y is small or zero at solar minimum. BIGG, E. K . , K v I z , Z., AND THOMPSON, ~V. J . , 1972. A n O c t o b e r influx of s u b m i c r o n particles into t h e lower s t r a t o s p h e r e . J. Geophys. Res. 77, 3916 3923. A l t h o u g h t h e c o n c e n t r a t i o n o f particles in t h e s t r a t o s p h e r e a b o v e t h e sulfate layer has b e e n f o u n d to be t y p i c a l l y 2 - 8 c m -s STP, on t h r e e occasions over t h e U n i t e d S t a t e s a n d four over Australia, c o n c e n t r a t i o n s g r e a t e r b y at least two orders of m a g n i t u d e h a v e b e e n e n c o u n t e r e d . The particles h a v e m o d a l d i a m e t e r s o f a b o u t 0.05/zm b u t are o f t e n j o i n e d t o g e t h e r to f o r m chains. I n a p p e a r a n c e a n d size distrib u t i o n t h e y closely r e s e m b l e t h e p a r t i c l e s o b t a i n e d on some rocket flights a t levels a b o v e 60km. P h e n o m e n a t h a t m a y be r e l a t e d a n d h a v e been o b s e r v e d to occur a t t h e s a m e t i m e o f y e a r are s t r a t o s p h e r i c aerosol layers, w h i c h a p p e a r optically d e n s e w h e n t h e y are viewed horizont a l l y looking t o w a r d t h e sun, a n d s o m e t w i l i g h t striations. The origin o f t h e particles has n o t been determined. BLANDER, M., 1972. T h e r m o d y n a m i c p r o p e r ties o f o r t h o p y r o x e n e s a n d c l i n o p y r o x e n e s b a s e d on t h e ideal t w o - s i t e model. Geochi~t. Cosmochim. Acta 36, 787-799. As a c o n s e q u e n c e o f t h e s t r o n g p r e f e r e n c e of Ca 2+ ions for M2 sites in c l i n o p y r o x e n e s , t h e Fe2+/Mg 2+ ratios in c l i n o p y r o x e n e s in e q u i l i b r i u m w i t h a g i v e n o r t h o p y r o x e n e are v e r y sensitive t o Ca 2+ c o n t e n t . This places in d o u b t t h e use o f t h e Fe2+-Mg 2+ e x c h a n g e equilibria b e t w e e n clino a n d o r t h o p y r o x e n e s as a " t h e r m o m e t e r " a n d m e a n s t h a t t h e Ca 2+ c o n t e n t o f c l i n o p y r o x e n e s m u s t b e a c c u r a t e l y k n o w n for m e a n i n g f u l t h e r m o d y n a m i c analyses. All available d a t a on Fe2+ Mg 2+ e x c h a n g e equilibria b e t w e e n M1 a n d M2 sites in o r t h o p y r o x e n e s a n d b e t w e e n olivine a n d o r t h o p y r o x e n e p h a s e s h a v e been r e a n a l y z e d a n d can be fit to t h e ideal t w o - s i t e m o d e l o f Mueller w i t h only t w o free e n e r g y p a r a m e t e r s . T h e s t a n d a r d free e n e r g y for

METEORS AND METEORITES

e x c h a n g e b e t w e e n M1 a n d M2 sites, AGE ° , w h i c h is c o n s i s t e n t w i t h all t h e d a t a f r o m 9 0 0 1300°C is 3.6keal/gfw, t h e s a m e v a l u e as was d e d u c e d b y Virgo a n d H a f n e r f r o m M S s s b a u e r d a t a for t h e r a n g e 600-1000°C. T h e free e n e r g y c h a n g e , ZJGT°, for t h e r e a c t i o n Fe2SiO4 + 2MgSiO3 ,~- Mg2SiO4 ÷ 2FeSiOa is 1.65kcal/gfw. F r o m this, t h e s t a n d a r d free e n e r g y of f o r m a t i o n of ferrosilite f r o m w u s t i t e a n d f~-cristoballite d e d u c e d a t 900°C is - 1 . 8 kcal/gfw. T h e ideal t w o - s i t e m o d e l is n o t c o n s i s t e n t w i t h m e a s u r e d a c t i v i t y coefficients in o r t h o p y r o x e n e s or in olivines, i n d i c a t i n g sign i f i c a n t c a n c e l l a t i o n of a c t i v i t y coefficient r a t i o s in t h e i o n - e x c h a n g e equilibria. CLEMESHA, B. R., AND NAXAMURA, Y., 1972. D u s t in t h e u p p e r a t m o s p h e r e . N a t u r e 237, 328-329. D u r i n g O c t o b e r , 1971, a large influx of dust occurred into the upper atmosphere at h e i g h t s a b o v e 30kin. T h e m a g n i t u d e of t h i s influx a p p e a r s to b e c o n s i d e r a b l y g r e a t e r t h a n a n y t h i n g p r e v i o u s l y r e p o r t e d . I t seems u n l i k e l y t h a t t h e d u s t was a local p h e n o m e n o n , b u t r a t h e r a n influx of e x t r a t e r r e s t r i a l m a t e r i a l . CRESSY, P. J . , JR., 1972. Cosmogenie radion u c l i d e s in t h e A l l e n d e a n d M u r c h i s o n c a r b o n a c e o u s c h o n d r i t e s . J . Geophys. Res. 77, 4 9 0 5 4911. M e a s u r e m e n t s were m a d e of 22iNIa, 26A1, S4Mn, a n d 6°Co p r o d u c e d b y cosmic r a y s in five s a m p l e s of t h e A l l e n d e C3 m e t e o r i t e a n d in one s p e c i m e n of M u r c h i s o n (C2); 46Sc, 4sV, 51Cr, a n d S7Co were also m e a s u r e d in several of t h e s e s a m p l e s . C o m p a r i s o n of o b s e r v e d A l l e n d e 6°Co a c t i v i t i e s w i t h c a l c u l a t e d n e u t r o n - c a p t u r e prod u c t i o n r a t e s yields a d e p t h scale for A l l e n d e t h a t a p p e a r s u n a m b i g u o u s t o a b o u t 30-cm d e p t h . U s i n g t h i s scale, t h e p r o d u c t i o n of 26A1 is c o n s t a n t (d:10%) to a d e p t h in excess of 3 0 c m , 22Na a c t i v i t y increases ~ 3 0 % f r o m n e a r t h e surface o f A l l e n d e t o 20- t o 30-cm d e p t h , a n d S4Mn p r o d u c t i o n increases ~ 5 0 % o v e r t h e s a m e d e p t h r a n g e . T h e a6Sc/S4Mn a c t i v i t y r a t i o is c o n s t a n t a t 0.059 ± 0 . 0 0 5 f r o m 8 t o 2 0 c m . M u r c h i s o n ' s 26A1 a c t i v i t y yields a c o s m i c - r a y e x p o s u r e age of 1.5 × 106 years. DELAETER, J . R., 1972. T h e isotopic comp o s i t i o n a n d e l e m e n t a l a b u n d a n c e o f g a l l i u m in m e t e o r i t e s a n d i n t e r r e s t r i a l samples. Geochim. Cosmoehim. A c t a 36, 735-743. T h e isotopic c o m p o s i t i o n of g a l l i u m in six i r o n m e t e o r i t e s a n d a t e r r e s t r i a l s t a n d a r d were m e a s u r e d u s i n g a solid source m a s s s p e c t r o m e t e r . I s o t o p i c a b u n dances of meteoritic and terrestrial gallium agree t o w i t h i n 0 . 1 1 % . T h e c o n c e n t r a t i o n of g a l l i u m in 21 iron a n d 5 s t o n e m e t e o r i t e s a n d in 13 s t a n d a r d rocks w a s d e t e r m i n e d u s i n g t h e m e t h o d of isotope d i l u t i o n . I n general, t h e

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agreement between this work and other published d a t a is excellent. DELAETER, J . R., 1972. T h e M u n d r a b i l l a m e t e o r i t e s h o w e r . . M e t e o r i t i c s 7, 285-294. A d e t a i l e d e x a m i n a t i o n o f t h e g e o g r a p h i c a l location, e x t e r n a l a p p e a r a n c e , m i c r o s t r u c t u r e , a n d c h e m i c a l c o m p o s i t i o n of t h e L o o n g a n a S t a t i o n , M u n d r a b i l l a a n d P r e m i e r D o w n s siderites h a s led t o t h e c o n c l u s i o n t h a t t h e y are all m e m b e r s of t h e one m e t e o r i t e shower. T h e cobalt, nickel, g a l l i u m a n d g e r m a n i u m c o n t e n t s o f four of t h e s e meteorites have been measured by X ray fluorescence s p e c t r o m e t r y a n d t h i s d a t a e n a b l e s t h e m to be classified as a n o m a l o u s , b u t p r o b a b l y r e l a t e d to C h e m i c a l G r o u p I. GOPAL, R., AND CALVO, C., 1972. S t r u c t u r a l r e l a t i o n s h i p of w h i t l o c k i t e a n d ]~Caa(POah. N a t u r e 237, 30-32. W h i t l o c k i t e occurs in biological s y s t e m s s u c h as d e n t a l calculi a n d o t h e r a b n o r m a l calcifications, i n l u n a r m a t e r i a l s a n d in m e t e o r i c samples. B e c a u s e t h e X r a y p o w d e r p a t t e r n of f~Caa(PO4) 2 a n d t h e m i n e r a l are n o t easily d i s t i n g u i s h e d , t h e t w o n a m e s h a v e been used interchangeably and synonymously. T h e a u t h o r s clarify t h e d i s t i n c t i o n s h o w i n g t h a t b y 900°C t h e t r a n s f o r m a t i o n h a d t a k e n place. P r e s u m a b l y t h e fact t h a t w h i t l o c k i t e t r a n s f o r m s t o ]3Ca3(PO4)2 a t t h i s low t e m p e r a t u r e will provide information concerning the thermal h i s t o r y of w h i t l o c k i t e a f t e r its f o r m a t i o n in geological s y s t e m s . GRAHAM, A. L., AND MASON, B., 1972. N i o b i u m in m e t e o r i t e s . Geochim. Cosmochim. A c t a 36, 917-922. S p a r k source m a s s s p e c t r o g r a p h i c a n a l y s e s of six c h o n d r i t e s a n d six a c h o n d r i t e s for n i o b i u m are r e p o r t e d . T h e g e o c h e m i c a l b e h a v i o r of n i o b i u m shows a r e l a t i v e c o h e r e n c e b e t w e e n t h e Ta, Ti, Z r c o n t e n t s of m e t e o r i t e s a n d l u n a r s a m p l e s a n d a lack of c o r r e l a t i o n w i t h Ca a n d A1. T h e d a t a p r o v i d e a m o r e s u b s t a n t i a l basis for t h e c h o n d r i t i c n i o b i u m a b u n d a n c e , w h i c h is e s t i m a t e d to b e 0 . 5 p p m , e q u i v a l e n t t o 0.9 atoms/106 a t o m s Si. HEMENWAY, C. L., HALLGREN, D. S., AND SCHNIAIJBERGER, D. C., 1972. S t a r d u s t . N a t u r e 238, 256-260. H e a v y m e t a l p a r t i c l e s h a v e b e e n d e t e c t e d in n o c t i l u c e n t clouds. P o s s i b l e sources for t h e s e p a r t i c l e s are c o n s i d e r e d a n d a solar origin is suggested. HERNDON, J . M., ROWE, M. W., LARSON, E. E., AND WATSON, D. E., 1972. M a g n e t i s m of m e t e o r i t e s : A r e v i e w o f R u s s i a n studies. Meteoritics 7, 263-284. T h e a u t h o r s p r e s e n t h e r e a s u m m a r y r e v i e w of t h e w o r k o f R u s s i a n scientists, p r i m a r i l y G u s ' k o v a a n d P o e h t a r e v , on the magnetism of meteorites. They have measured the initial natural remanent magn e t i z a t i o n a n d t h e m a g n e t i c s u s c e p t i b i l i t y in

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AFCRL BIBLIOGRAPHY--3RD Q U A R T E R 1972

m o r e t h a n 900 m e t e o r i t e s a m p l e s f r o m collections t h r o u g h o u t t h e Soviet U n i o n . More s o p h i s t i c a t e d studies, i n v o l v i n g b o t h t h e r m a l a n d a l t e r n a t i n g field d e m a g n e t i z a t i o n e x p e r i m e n t s , were also c o n d u c t e d o n a few samples. M e t e o r i t e s a l m o s t i n v a r i a b l y r e t a i n e v i d e n c e of a n c i e n t m a g n e t i c fields in t h e i r p r e t e r r e s t r i a l h i s t o r y . HUGHES, D. W., AND BAGGALEY, W. J., 1972. Effect o f sunrise o n t h e m e t e o r region. N a t u r e 237, 224-226. T h e a u t h o r s suggest t h a t a p o s t s u n r i s e increase in w i n d shears, w h i c h will be p r e s e n t o v e r t h e whole m e t e o r region u p to t h e t u r b o p a u s e ( 105 kin), is r e s p o n s i b l e for t h e c h a n g e in t h e o b s e r v e d echo d u r a t i o n d i s t r i b u t i o n for T ~< 8 s. O n t h e o t h e r h a n d t h e d r a s t i c r e d u c t i o n in t h e n u m b e r of echoes w i t h T > 12s in b o t h d a y t i m e a n d n i g h t - t i m e o b s e r v a t i o n s is definitely d u e to a loss of ionization. KERRIDGE, J., 1972. Cosmic a b u n d a n c e of iron a n d n a t u r e of p r i m i t i v e m a t e r i a l in m e t e o r ites. N a t u r e 239, 44-45. T h e a u t h o r p r e s e n t s a r g u m e n t s for a m i x t u r e h y p o t h e s i s w h e r e b y phyllosilicates, r e p r e s e n t i n g u n a l t e r e d m a t e r i a l , and magnetite, representing altered material, were m i x e d t o g e t h e r a t low t e m p e r a t u r e , p r e s u m a b l y o n t h e m e t e o r i t e p a r e n t b o d y , so t h a t t h e y n e v e r e q u i l i b r a t e d w i t h e a c h other. T h e " p r i m i t i v e e s s e n c e " of a T y p e I c a r b o n aceous m e t e o r i t e consists of its p h y l l o s i l i c a t e p o p u l a t i o n or a m a j or p a r t of it. T h i s h y p o t h e s i s , if correct, leads t o a n e w v a l u e for t h e cosmic a b u n d a n c e of iron of 5.3 ~_ 0.6 x l 0 s (relative to Si = 10 s) w h i c h is s e n s i b l y different f r o m t h e c o m m o n l y u s e d b u l k v a l u e of 9.0 ~ 0.5 × l 0 s, t h o u g h b o t h lie w i t h i n t h e u n c e r t a i n t y l i m i t s of t h e solar spectroscopic d a t a . KEI~IDGE, J . F., 1972. I r o n t r a n s p o r t in chondrites: evidence from the Warrenton m e t e o r i t e . Geochim. Cosmoehim. A c t a 36, 9 1 3 916. V e i n s of iron e n r i c h m e n t in a n olivine c h o n d r u l e in W a r r e n t o n are a t t r i b u t e d to m i g r a t i o n of iron p r i o r to final c o n s o l i d a t i o n . A q u e o u s t r a n s p o r t a l o n g c r a c k s is s u g g e s t e d as t h e m o s t p l a u s i b l e m e c h a n i s m r e s p o n s i b l e for s u c h m i g r a t i o n , w i t h possible i m p l i c a t i o n s for " m e t a m o r p h i c " t h e o r i e s of iron d i s t r i b u t i o n in chondrites. LAVRUKHINA, A. K., AND USTINOVA, G. K., 1972. Cosmogenic r a d i o n u c l i d e s in s t o n e s a n d m e t e o r i t e orbits. E a r t h Planet. Sci. Lett. 15, 347-360. D e p t h d i s t r i b u t i o n s of 14 c o s m i c - r a y p r o d u c e d r a d i o n u c l i d e s in c h o n d r i t e s a n d a c h o n d r i t e s of different sizes h a v e b e e n c a l c u l a t e d . T h e d e p e n d e n c e of d e p t h d i s t r i b u t i o n s of different r a d i o n u c l i d e s o n c o m p o s i t i o n s a n d p r e a t m o s p h e r i c sizes of m e t e o r i t e s , on t e m p o r a l a n d s p a t i a l v a r i a t i o n s of cosmic r a y s h a s b e e n i n v e s t i g a t e d . T h e r e is a n " o r b i t a l effect" in

cosmogenie r a d i o n u c l i d e a c c u m u l a t i o n owing to t h e l i m i t a t i o n of t h e m o d u l a t i o n r a n g e (the u p p e r l i m i t is a t 1 . 9 A U f r o m t h e S u n ) : in m e t e o r i t e s w i t h large o r b i t s t h e a c t i v i t i e s of r a d i o n u c l i d e s m u s t b e h i g h e r d u e to t h e bomb a r d m e n t of t h e m e t e o r i t e s b y u n m o d u l a t e d cosmic rays d u r i n g a p a r t of t h e i r way. T h u s , r a d i o n u c l i d e a c t i v i t y c a n b e a c r i t e r i o n for t h e sizes of m e t e o r i t e orbits. A c c o r d i n g to t h e k n o w n m e t e o r i t e o r b i t s t h e following d e p e n d e n c e for meteorites with aphelia more distant than 1 . 9 A U h a s b e e n d e r i v e d : q" = 1.25 + 0.13 z + 0.53;-l w h e r e q' is a n a p h e l i o n in AU, z = tmoa/to,b, torb is t h e flight t i m e a l o n g t h e orbit, tmod is t h e flight t i m e in t h e m o d u l a t i o n range. B y a n a l y s i n g 26A1 a c t i v i t i e s in 44 h y p e r s t h e n e , 29 b r o n z i t e , 4 e n s t a t i t e c h o n d r i t e s , a n d 23 a c h o n d r i t e s , t h e a p h e l i a of t h e s e s t o n e s h a v e b e e n d e t e r m i n e d . The chondrite distributions vs aphelia have m a x i m a b e t w e e n 1.9 a n d 2 . 5 A U . Therefore, as m o s t c h o n d r i t e s h a v e a s e m i m a j o r axis a ~ 1.51.7AU, one m a y suppose a c c o r d i n g to t h e m o d e l c a l c u l a t i o n s of A n d e r s a n d Mellick b y t h e M o n t e Carlo m e t h o d t h a t c h o n d r i t e p a r e n t bodies were a s t e r o i d s of t h e Mars f a m i l y (similar to 2 P a l l a s or 1310 Villigeria) or of t h e Apollo f a m i l y (similar to 1685 Toro). A c h o n d r i t e s m a y h a v e a n o t h e r origin. T h e p r o p o s e d m e t h o d for c a l c u l a t i n g t h e sizes of m e t e o r i t e o r b i t s comb i n e d w i t h t h e m e t h o d of visible r a d i a n t s m a k e s it possible t o o b t a i n all o r b i t p a r a m e t e r s (a, e, i, q, q') for t h e m e t e o r i t e s w i t h k n o w n a t m o s p h e r i c trajectories. MANUEL, O. K., '~VRIGHT, I~. J., MILLER, D. K., AND KURODA, P. K., 1972. Isotopic c o m p o s i t i o n s of r a r e gases in t h e c a r b o n a c e o u s c h o n d r i t e s Mokoia a n d Allende. Geochim. Cosmochim. A c t a 36, 961-983. T h e isotopic compositions have been measured mass spectrometrically for n e o n , argon, k r y p t o n , a n d x e n o n released from the carbonaceous chondrites Mokoia and A l l e n d e in stepwise h e a t i n g e x p e r i m e n t s . T h e isotopic c o m p o s i t i o n s of r a r e gases released f r o m t h e m e t e o r i t e s a t different t e m p e r a t u r e s v a r i e d quite considerably. The observed minimum and m a x i m u m values were, for e x a m p l e , as follows: Ne2°/Ne22 -2.10 (Allende 800°C) a n d 12.95 (Mokoia 400°C); Ar36/AraS = 4.20 (Allende 1600°C) a n d 6.05 (Allende 800°C); KrS4/KrS6 = 3.140 (Allende 1000°C) a n d 3.306 (Mokoia 600°C); X e 1 3 4 / X e l a 6 = l . 0 1 9 (Allende 800°C) a n d 1.192 (Allende 1400°C). A m a r k e d enrichm e n t of Xe129 d u e to t h e d e c a y of e x t i n c t n u c l i d e I ~29 was o b s e r v e d in b o t h m e t e o r i t e s . T h e v a r i a t i o n s of t h e isotopic r a t i o s are p a r t l y c a u s e d b y t h e p r e s e n c e of c o s m i c - r a y s p a l l a t i o n a n d neutron-capture products. In addition, however, a m a r k e d t r e n d of m a s s - d e p e n d e n t v a r i a t i o n of

METEORS A N D METEORITES

t h e isotopic r a t i o s w a s o b s e r v e d in t h i s w o r k . T h e r a r e gas isotopes released f r o m t h e m e t e o r i t e s a p p e a r to be s y s t e m a t i c a l l y m a s s - f r a c t i o n a t e d r e l a t i v e t o t h e r e l a t i v e a b u n d a n c e s of t h e a v e r a g e c a r b o n a c e o u s c h o n d r i t e (AVCC). I t seems t h a t t h i s p h e n o m e n o n c a n b e b e s t e x p l a i n e d as d u e t o t h e f a c t t h a t t h e r e e x i s t r e s e r v o i r s of t w o isotopically d i s t i n c t gases in t h e m e t e o r i t e s a n d m i x t u r e s of t h e s e gases are b e i n g released a t e a c h t e m p e r a t u r e fraction. T h e t w o different gases b e i n g c o n s i d e r e d h e r e are m o s t likely t h e so-called solar a n d p l a n e t a r y r a r e gases, w h o s e isotopic c o m p o s i t i o n s are q u i t e different from each other. MASON, B., 1972. T h e m i n e r a l o g y of m e t e o r i t e s . Meteoritics 7, 309-326. D u r i n g t h e p a s t d e c a d e t h e n u m b e r of m i n e r a l s r e c o g n i z e d in m e t e o r i t e s h a s d o u b l e d , f r o m a b o u t 40 in 1962 to o v e r 80 in 1972. T h e g r e a t e x p a n s i o n in o u r k n o w l e d g e c a n b e largely a s c r i b e d t o t h e i n t r o d u c t i o n o f t h e e l e c t r o n - b e a m m i c r o p r o b e as a r e s e a r c h tool, e n a b l i n g t h e q u a n t i t a t i v e a n a l y s i s of microscopic g r a i n s in p o l i s h e d sections. W h i l e m o s t of t h e s e discoveries arc of m i n e r a l s p r e s e n t in m i n u t e a m o u n t s , t h e i r i d e n t i f i c a t i o n h a s e l u c i d a t e d m a n y a s p e c t s of m e t e o r i t e f o r m a t i o n . O f p a r t i c u l a r i n t e r e s t are five p h o s p h a t e m i n e r a l s , t h r e e of t h e m u n k n o w n in t e r r e s t r i a l r o c k s ; a c h r o m i u m n i t r i d e a n d a silicon oxyn i t r i d e ; l o n s d a l e i t e a n d chaoite, n e w p o l y m o r p h s of c a r b o n ; r i n g w o o d i t e a n d m a j o r i t e , t h e spinel a n d g a r n e t a n a l o g s of olivine a n d p y r o x e n e r e s p e c t i v e l y ; a n u m b e r of calcium- a n d a l u m i n u m - r i c h silicates in t h e A l l e n d e m e t e o r i t e , a T y p e I I I c a r b o n a c e o u s c h o n d r i t e w h i c h fell in I 9 6 9 ; a n d several alkali-rich silicates f o u n d as inclusions in iron m e t e o r i t e s . K n o w l e d g e of t h e c o m p o s i t i o n a l r a n g e of t h e c o m m o n m i n e r a l s olivine, p y r o x e n e , a n d plagioelase h a s also b e e n g r e a t l y i n c r e a s e d b y r e c e n t researches. MEADOWS, A. J . , 1972. R e m a n e n t m a g n e t i z a t i o n in m e t e o r i t e s . Nature 237, 274. T h e a u t h o r proposes two mechanisms by which natural r e m a n e n t m a g n e t i s m could h a v e b e e n c r e a t e d in m e t e o r i t e s . OSBO~N, T. W., 1972. E v i d e n c e for a s s o c i a t i o n b e t w e e n I r a n d A1 in L c h o n d r i t e s . Nature 239, 10-11. A n a s s o c i a t i o n b e t w e e n Ir, A1, Sc, Ca, a n d r a r e e a r t h e l e m e n t s h a s b e e n e s t a b l i s h e d in c h o n d r u l e s e x t r a c t e d f r o m o r d i n a r y a n d carb o n a c e o u s c h o n d r i t e s b y O s b o r n a n d coworkers. To i n v e s t i g a t e t h e n a t u r e of t h e A l ~ r a s s o c i a t i o n f u r t h e r , t h e a u t h o r h a s p l o t t e d t h e w h o l e chond r i t e a b u n d a n c e of Ir, a n d t h e A1 a b u n d a n c e s for t h e s a m e c h o n d r i t e s . T e n of t h e e l e v e n L c h o n d r i t e s p l o t t e d s h o w a definite p o s i t i v e t r e n d . T h e d i s t r i b u t i o n of I r a n d A1 m a y b e c o n t r o l l e d g e o c h e m i c a l l y b y t h e siderophilic a n d l i t h o p h i l i c

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c h a r a c t e r of I r a n d A1, or t h e d i s t r i b u t i o n m a y be controlled cosmochemically by condensation. PODOSEK, F. A., 1972. Gas r e t e n t i o n c h r o n o logy of P e t e r s b u r g a n d o t h e r m e t e o r i t e s . Geoehim. Cosmochim. Acta 36, 755-772. A r g o n a n d x e n o n d a t a are p r e s e n t e d for a t h e r m a l release s t u d y on a n e u t r o n - i r r a d i a t e d s a m p l e o f t h e eucrite m e t e o r i t e P e t e r s b u r g . X e n o n spallat i o n c o r r e c t i o n s are m a d e b y t h e m e t h o d o f correlation systematics, and the relationship of lunar systematics to the systematics derived for t h e A n g r a dos Reis m e t e o r i t e is discussed. C o r r e l a t i o n s y s t e m a t i c s are also u s e d in ree v a l u a t i o n of n e u t r o n - a c t i v a t i o n x e n o n d a t a for o t h e r m e t e o r i t e s in w h i c h s p a l l a t i o n effects are p r o m i n e n t . P e t e r s b u r g h a s n o excess X e 129 a t t r i b u t a b l e to in situ d e c a y of I t29, a n d a 1)u2aa/u 2as r a t i o c o r r e s p o n d i n g t o o n s e t of x e n o n r e t e n t i o n 146 ± 14 million y e a r s a f t e r t h e c h o n d r i t e St. Severin. T h e a r g o n d a t a show s u b s t a n t i a l loss of radiogenic A r *° a n d do n o t define a n Ar*°-Ara9 p l a t e a u , e s t a b l i s h i n g a lower l i m i t K - A r age of 4.35 × 109 yr, r e l a t i v e to a n a s s u m e d age of 4.60 × 109 y r for St. Severin. C o m p a r i s o n w i t h s t r o n t i u m d a t a for o t h e r eucrites a n d t h e c h o n d r i t e G u a r e f i a suggests a n i n t e r v a l of 220 million y e a r s b e t w e e n f r a c t i o n a t i o n f r o m a r u b i d i u m - r i c h r e s e r v o i r a n d t h e final cooling of P e t e r s b u r g . T h e c a l c i u m - r i c h a c h o n drite Lafayette has no detectable decay products of e i t h e r 1129 or P u TM, i n d i c a t i n g a g a s - r e t e n t i o n f o r m a t i o n t i m e a t l e a s t 350 million y e a r s a f t e r St. Severin. T h e c u r r e n t b e s t v a l u e of t h e Pu24*/U 23s r a t i o in t h e c h o n d r i t e St. S e v e r i n a t t h e t i m e of its f o r m a t i o n is 0.0154 ± 0.0014, 21% higher than previously reported. REED, S. J . B., t972. D e t e r m i n a t i o n of Ni, Ga, a n d Ge i n iron m e t e o r i t e s b y X - r a y fluorescence analysis. Meteoritics 7 , 2 5 7 - 2 6 2 . A l t h o u g h n e u t r o n a c t i v a t i o n a n a l y s i s for t r a c e G a a n d Ge is m o r e s e n s i t i v e a n d possibly m o r e a c c u r a t e , X r a y fluorescence a n a l y s i s is quicker, uses r e a d i l y a v a i l a b l e e q u i p m e n t , a n d is n o n d e s t r u c t i v e . I t is s h o w n t h a t Ga, Ge, a n d N i c a n b e d e t e r m i n e d b y X r a y fluorescence o n m e t a l l o g r a p h i c polished m o u n t s sufficiently a c c u r a t e l y for classification a c c o r d i n g to W a s s o n ' s c h e m i c a l groups. R e s u l t s are g i v e n for 45 irons, i n c l u d i n g some n o t p r e v i o u s l y classified. SANTOLIQUIDO, P. M., AND EItMANN, W . D., 1972. B i s m u t h in s t o n y m e t e o r i t e s a n d s t a n d a r d rocks. Geochim. Cosmochim. Acta 36, 897 902. Bismuth has been determined by alpha counting of t h e 21°po d a u g h t e r a c t i v i t y of t h e 21°Bi formed by thermal neutron activation. Results are p r e s e n t e d for t h i r t y e h o n d r i t e s , six a c h o n drites, e i g h t s e p a r a t e d m e t e o r i t i c phases, a n d six U.S. Geological S u r v e y s t a n d a r d rocks. T h e r e

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AFCRL B I B L I O G R A P I I Y - - 3 R D QUARTER 1 9 7 2

is n o r e s o l v a b l e difference in B i a b u n d a n c e s a m o n g t h e different g r o u p s of o r d i n a r y chondrites. B i s m u t h c o n c e n t r a t i o n decreases w i t h i n c r e a s i n g petrologic g r a d e a m o n g t h e o r d i n a r y c h o n d r i t c s . T h e e n s t a t i t c c h o n d r i t e s are separable i n t o t w o g r o u p s o n t h e basis of B i d a t a . SCHULTZ, L., SIGNER, P., LOl~IN, J. C., AND PELLAS, P., 1972. C o m p l e x i r r a d i a t i o n h i s t o r y of t h e W e s t o n c h o n d r i t e . Earth Planet. Sci. Lett. 15, 403-410. H e l i u m , n e o n , a n d a r g o n were a n a l y s e d in s e v e n different l i g h t inclusions of t h e gas-rich c h o n d r i t e W e s t o n . T r a c k s p r o d u c e d b y galactic cosmic r a y s were c o u n t e d i n some of t h e s e x e n o l i t h s . One of t h e x e n o l i t h s c o n t a i n s a p p r o x i m a t e l y 2 0 % m o r e spallogenic gases t h a n t h e o t h e r s . T h i s gas excess is p a r a l l e l e d b y a t r a c k excess a n d c a n n o t b e e x p l a i n e d b y a d e p t h effect or b y differences in t h e c h e m i c a l composit i o n . T h e e x p l a n a t i o n of t h e n o b l e gas a n d t r a c k excess w h i c h a c c o u n t s for all o b s e r v a t i o n s is a n e x p o s u r e of t h e p a r t i c u l a r x e n o l i t h to cosmic i r r a d i a t i o n p r i o r to c o m p a c t i o n of t h e m e t e o r o i d . SHOWALTER, D. L., WAKITA, ~-~., AND SCHMITT, g . A., 1972. R a r e e a r t h a n d o t h e r a b u n d a n c e s in t h e M u r c h i s o n c a r b o n a c e o u s m e t e o r i t e . Meteoritics 7, 295-301. T h e a b u n d a n c e s of 27 e l e m e n t s are r e p o r t e d for t h e M u r c h i s o n m e t e o r i t e . N i n e of t h e s e e l e m e n t s (A1, Ca, Fe, Mn, Na, K, Cr, Co, a n d So) h a v e b e e n d e t e r m i n e d p r e v i o u s l y for different M u r c h i s o n specimens. A b u n d a n c e s for 18 e l e m e n t s (In, Cd, V, Y, a n d R E E ) are n e w d a t a for t h i s m e t e o r i t e . T h e c h e m i c a l comp o s i t i o n is s i m i l a r to t h e t y p e I I c a r b o n a c e o u s c h o n d r i t e s , p a r t i c u l a r l y on t h e basis of R E E , Mn, a n d I n a b u n d a n c e s . WASSON, J . T., 1972. F o r m a t i o n of o r d i n a r y c h o n d r i t e s . Rev. Geophys. Space Phys. 1O, 711-759. Most of t h e c h e m i c a l a n d m i n e r a l o g i c a l p r o p e r t i e s o f t h e o r d i n a r y c h o n d r i t e s were e s t a b l i s h e d b y processes t h a t o c c u r r e d in t h e solar n e b u l a d u r i n g a s h o r t t i m e s p a n n e a r t h e t i m e of f o r m a t i o n of t h e solar s y s t e m . F o u r separate and distinct fractionation events appear to have been involved in their formation from more primitive material of mean solar-system c o m p o s i t i o n . I n o r d e r of o c c u r r e n c e t h e s e were (1) a r e f r a c t o r y - e l e m e n t f r a c t i o n a t i o n , w h i c h r e s u l t e d in t h e lower Mg/Si, Ca/Si, A1/Si a n d o t h e r r e f r a c t o r y - e l e m e n t / S i r a t i o s r e l a t i v e to C1 c h o n d r i t e s ; (2) a s i d e r o p h i l i c - e l e m e n t f r a c t i o n a tion, w h i c h p r o d u c e d t h e m o n o t o n i c r e d u c t i o n of s i d e r o p h i l i c - e l e m e n t / S i r a t i o s as one proceeds from the tt group toward the LL group and the v a r i a t i o n in r a t i o s of one siderophilie e l e m e n t to a n o t h e r t h r o u g h t h i s s e q u e n c e ; (3) a f r a e t i o n a t i o n of slightly volatile e l e m e n t s (such as Cu, Ga, a n d Ge), p r o b a b l y d u r i n g c h o n d r u l e f o r m a t i o n ; a n d (4) a f r a e t i o n a t i o n of h i g h l y volatile elements,

p r o b a b l y b y t h e r m a l m e t a m o r p h i s m while t h e c h o n d r i t i c m a t e r i a l was s t o r e d m p l a n e t e s i m a l s of t h e m e t e r - t o - 1 0 O - m e t e r size range. I n e a c h of t h e four cases t h e m o s t p l a u s i b l e f r a e t i o n a t i o n m e c h a n i s m i n v o l v e s a s e p a r a t i o n of gases f r o m solids. T h e a m b i e n t t e m p e r a t u r e in t h e p l a n e t a r y p o r t i o n of t h e solar n e b u l a d u r i n g t h e f o r m a t i o n of t h e s e c h o n d r i t e s a p p e a r s to h a v e b e e n charact e r i z e d b y two m a x i m u m s . MOON--GENERAL ALFV]~N, H., AND ARRHENIUS, G., 1972. Origin a n d e v o l u t i o n of t h e E a r t h - M o o n s y s t e m . The Moon 5, 210-230. See Origin of t h e Solar System. ANDERSON, D. L., 1972. T h e origin of t h e Moon. Nature 239, 263 265. E x p l a n a t i o n of t h e M o o n ' s c o m p o s i t i o n in a m o d e l for t h e cond e n s a t i o n of t h e p l a n e t s f r o m a cloud of solar c o m p o s i t i o n suggests t h a t t h e M o o n a c c r e t e d a t h i g h e r t e m p e r a t u r e s a n d lower pressures t h a n t h e t e r r e s t r i a l p l a n e t s . T h i s m a y b e e x p l a i n e d if t h e l u n a r o r b i t initially h a d a h i g h i n c l i n a t i o n . SINGER, S. F., 1972. Origin Gf t h e M o o n b y t i d a l c a p t u r e a n d some g e o p h y s i c a l consequences. The Moon 5, 206 209. O f t h e m a n y p r o p o s e d m o d e s of origin of t h e Moon, some violate p h y s i c a l laws ; m a n y are in conflict w i t h o b s e r v a t i o n s ; all are i m p r o b a b l e . P e r h a p s t h e l e a s t i m p r o b a b l e - - b a s e d on r e c e n t t i d a l t h e o r y c a l c u l a t i o n s a n d o n t h e i n t e r p r e t a t i o n of l u n a r rock d a t a - - i s c a p t u r e o f t h e M o o n as it p a s s e d n e a r t h e E a r t h in a d i r e c t (prograde) orbit, s h o r t l y a f t e r t h e f o r m a t i o n of Moon a n d E a r t h , a b o u t 4.5 billion y e a r s ago. ( C a p t u r e of t h e Moon f r o m a n i n i t i a l l y r e t r o g r a d e o r b i t w h i c h h a d b e e n p r o p o s e d some y e a r s ago, leads to p h y s i c a l l y u n a c c e p t a b l e consequences.) Tile effects of c a p t u r e on t h e E a r t h w o u l d h a v e b e e n c a t a c l y s m i c , l e a d i n g t o i n t e n s i v e h e a t i n g o f its interior, to v o l c a n i s m , a n d t o t h e i m m e d i a t e f o r m a t i o n of a n a t m o s p h e r e a n d h y d r o s p h e r e . T h u s c a p t u r e o f a M o o n m a y h a v e g i v e n rise to t h e u n i q u e p r o p e r t i e s o f t h e E a r t h (in t h e Solar S y s t e m ) a n d to t h e e a r l y e v o l u t i o n of life, a b o u t 3.5 billion y e a r s ago. MOON--ATMOSPHERE BRODZINSKI, R . L., 1972. R a d o n - 2 2 2 in t h e l u n a r a t m o s p h e r e . Nature 238, 107-109. T h e effects of t h e l u n a r v a c u u m a n d t h e w i d e l y v a r y i n g surface t e m p e r a t u r e s are p r o b a b l y t h e p h e n o m e n a m o s t r e s p o n s i b l e for t h e d i s t r i b u t i o n o f r a d o n o n t h e M o o n ' s surface. This is n o t t o suggest t h a t t h e d i s t r i b u t i o n of r a d o n is c o n s t a n t , b u t t h a t its c o n c e n t r a t i o n a t a n y g i v e n l o c a t i o n

M O O N - - F I G U R E AND INTERNAL STI~UCTURE is p r o b a b l y m o s t affected b y t h e t e m p e r a t u r e a n d t h e t i m e of t h e l u n a r day. T h u s t h e l o c a t i o n of t h e s a m p l i n g s t a t i o n will d e t e r m i n e t h e r a t e of temperature change; with warming, trapped i n t e r s t i t i a l r a d o n w o u l d be released m o r e r a p i d l y as its k i n e t i c e n e r g y increases, while d u r i n g cooling t h e surface h a s b e e n " b a k e d o u t " a n d r a d o n effusion will a p p r o a c h a m i n i m u m . HODGES, R. R., JR., HOFFMAN, J. H., YEH, T. T. J., AND CIIANG, ~. K., 1972. Orbital search for lunar volcanism. J. Geophys. Res. 77, 4079-4085. The total rate of volcanic release of gases into the lunar atmosphere is estimated to be less than 60g/sec. One of the implications of this degassing is that, if it occurs as sporadic releases of large quantities of gas, these events can be detected by an orbiting mass spectrometer, such as that carried on the flight of Apollo 15 and one that will operate during the Apollo 16 mission. The nature of a volcanic perturbation of the lunar atmosphere is discussed, and a lower bound is derived for the expected time between detected events. MOON--FIGURE TURE

AND INTERNAL

STRUC-

BEALS, C. S., 1972. L a v a filled c r a t e r s a n d t h e t h e r m a l h i s t o r y of t h e l u n a r surface. N a t u r e 237, 226-227. See M o o n - - S u r f a c e L a y e r . CAP, F. F., 1972. Possible p r o d u c t i o n m e c h a n i s m s of l u n a r m a g n e t i c fields. J . Geophys. Res. 77, 3328-3333. T h e i m p o s s i b i l i t y of t h e p r o d u c t i o n of local surface m a g n e t i c fields o n t h e m o o n b y c o n d u c t i o n c u r r e n t s in t h e l u n a r soil a n d i n local l u n a r a t m o s p h e r e s b y v o l c a n i c e r u p t i o n is shown. H o w e v e r , i t is s u g g e s t e d t h a t c o n v e c t i o n c u r r e n t s p r o d u c e d b y t h e i o n i z a t i o n (by radia t i o n a n d / o r b y t r i b o e l e c t r i c effects) of volcanica s h - p a r t i c l e flows m a y p r o d u c e t h e local magn e t i c fields of a b o u t 1O00~ t h a t are b e l i e v e d t o h a v e e x i s t e d o n t h e m o o n a b o u t 3.5 x 109 y e a r s ago. A simple e l e c t r o - g a s - d y n a m i c m o d e l for s u c h flows a n d e x p e r i m e n t s for f u r t h e r investig a t i o n of t h i s h y p o t h e s i s are discussed. DumA, A., HEARD, H . C., AND SCHOCK, R . N., 1972. T h e l u n a r t e m p e r a t u r e profile. E a r t h Planet. Sci. Lett. 15, 301-304. See M o o n - Temperature. DYAL, P., PARKIN, C. W., SNYDER, C. W., AND CLAY, D. n . , 1972. M e a s u r e m e n t s of l u n a r m a g n e t i c field i n t e r a c t i o n w i t h t h e solar w i n d . N a t u r e 236, 381-385. T h e r e m a n e n t m a g n e t i c field a t t h e l u n a r surface is c o m p r e s s e d as m u c h as 4 0 % a b o v e its initial v a l u e b y t h e solar w i n d , b u t t h e t o t a l r e m a n e n t m a g n e t i c p r e s s u r e is less t h a n t h e s t a g n a t i o n p r e s s u r e b y a f a c t o r of six, i m p l y i n g t h a t a local s h o c k is n o t f o r m e d .

79

GAST, P. W., 1972. T h e c h e m i c a l c o m p o s i t i o n a n d s t r u c t u r e of t h e Moon. M o o n 5, 121-148. T h r e e t y p e s of igneous rocks, all u l t i m a t e l y r e l a t e d to b a s a l t i c liquids, a p p e a r t o be c o m m o n on t h e l u n a r surface. T h e y are : ( 1 ) i r o n - r i c h m a r e b a s a l t s , (2) U-, R E E - , a n d Al-rich b a s a l t s ( K R E E P ) , a n d (3) plagioclase-rich or a n o r t h o sitic rocks. All t h r e e rock t y p e s are d e p l e t e d in e l e m e n t s m o r e volatile t h a n s o d i u m a n d in t h e siderophile e l e m e n t s w h e n r e l a t i v e e l e m e n t a b u n d a n c e s are c o m p a r e d w i t h t h o s e of c a r b o n aceous c h o n d r i t e s . T h e c h e m i s t r y a n d age r e l a t i o n s h i p s of t h e s e rocks suggest t h a t t h e y are d e r i v e d f r o m a feldspathic, r e f r a c t o r y element-rich interior that becomes more pyrox e n i t i e ; t h a t is, i r o n / m a g n e s i u m - r i c h ; w i t h d e p t h . I t is s u g g e s t e d t h a t t h e d e e p e r p a r t s of the lunar interior tend toward ehondritie e l e m e n t a b u n d a n c e s . T h e r a d i a l v a r i a t i o n in mineralogy and bulk chemical composition i n f e r r e d f r o m t h e surface c h e m i s t r y is p r o b a b l y a p r i m i t i v e f e a t u r e of t h e Moon t h a t reflects t h e a c c r e t i o n of r e f r a c t o r y e l e m e n t - e n r i c h e d m a t e r i als l a t e in t h e f o r m a t i o n of t h e b o d y . GOSE, W. A., PEARCE, G. W., STRANGWAY, D. W., AND LARSON, E . E., 1972. O n t h e applica b i l i t y of l u n a r breccias for p a l e o m a g ] , e t i c i n t e r p r e t a t i o n s . M o o n 5, 106-120. M a n y of t h e breccias r e t u r n e d b y t h e Apollo m i s s i o n s are c a p a b l e of a c q u i r i n g a s u b s t a n t i a l viscous r e m a n e n t m a g n e t i z a t i o n (VRM) w h i c h is of t w o forms. T h e first one h a s a n u p p e r l i m i t t o t h e r e l a x a t i o n t i m e s of a b o u t 100 to 1000rain w h i c h c o r r e s p o n d s to a g r a i n d i a m e t e r of a b o u t 145A. This suggests t h a t t h e m a x i m u m r e l a x a t i o n t i m e is d e t e r m i n e d b y t h e t r a n s i t i o n f r o m superp a r a m a g n e t i e to s t a b l e single d o m a i n particles. T h e second f o r m of V R M follows t h e classical logt d e p e n d e n c e t y p i c a l for m u l t i d o m a i n g r a i n s w i t h a wide d i s t r i b u t i o n of r e l a x a t i o n times. H y s t e r e s i s loop m e a s u r e m e n t s yield t h e s a m e k i n d of g r a i n size d i s t r i b u t i o n s . I n a d d i t i o n t h e a n a l y s i s shows a fivefold e n r i c h m e n t of n a t i v e iron i n t h e breccias a n d soils as c o m p a r e d t o t h e igneous rocks. I n spite of a large V R M some b r e c e i a s c o n t a i n a s t a b l e remanenV m a g n e t i z a tion. I t s i n t e n s i t y is t y p i c a l l y 1 0 - % m u / g , t h e s a m e v a l u e f o u n d for igneous rocks. I t is possible, t h e r e f o r e , t o use some of t h e breccias t o rec o n s t r u c t t h e h i s t o r y of t h e l u n a r m a g n e t i c field. ttELSLEY, C. E., 1972. T h e significance of t h e m a g n e t i s m o b s e r v e d in l u n a r rocks. The M o o n 5, 158-160. P a r t i a l t h e r m a l r e m a n e n c e e x p e r i m e n t s o n l u n a r igneous rocks i n d i c a t e t h a t t h e m a g n e t i z a t i o n of l u n a r rocks is n o t a n o r m a l single component thermoremanent magnetization. The magnetization therefore may not have been a c q u i r e d a t t h e t i m e of i n i t i a l cooling of t h e

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AFCRL BIBLIOGRAPItY--31~D QUARTER 1972

rock a n d t h u s should be u s e d c a u t i o u s l y in making estimates of the intensity of the ancient l u n a r m a g n e t i c field. HULME, G., 1972. Mascons a n d isostasy. N a t u r e 238, 448-450. The a u t h o r shows t h a t t h e p o s i t i v e g r a v i t y anomalies a s s o c i a t e d w i t h circular m a r i a do n o t necessarily i m p l y t h a t a large p a r t o f t h e i n t e r i o r of t h e Moon is cold. The a n o m a l i e s could be p r o d u c e d e v e n if t h e Moon c a n n o t s u p p o r t stress differences below d e p t h s o f t h e o r d e r of 100km. B e t t e r k n o w l e d g e of the topography, more detailed gravity s u r v e y s , a n d m o r e e v i d e n c e f r o m seismology will allow t h e d e t e r m i n a t i o n of t h e t r u e s t r u c t u r e o f t h e maria. I~ttABIBULLIN, SH. T., AND CHIKANOV, YU. A., 1972. Coefficients C2o a n d C22 in t h e e x p a n s i o n o f t h e M o o n ' s g r a v i t y field. Soy. A s t r o n . - - A J 16, 179-180. I t is p r o p o s e d t h a t t h e m o s t p r o b a b l e values for t h e inclination o f t h e Cassini e q u a t o r to t h e ecliptic a n d t h e p a r a m e t e r g' d e s c r i b i n g t h e radial d e n s i t y d i s t r i b u t i o n in t h e l u n a r i n t e r i o r be a d o p t e d as a criterion for a c c e p t i n g values of t h e coefficients C2o a n d C22. RANSFORD, G., AND SZOGI~EN, W., 1972. Moon m o d e l - - A n offset core. N a t u r e 238, 260 262. A l u n a r m o d e l h a v i n g a n a s y m m e t r i c core explains t h e offset c e n t r e o f g r a v i t y , m o m e n t of inertia, m a s c o n s , a n d m a r i a . A possible e v o l u t i o n t h e o r y is also p r e s e n t e d . WOLLENtIAUPT, W . R., OSBURN, R. K . , AND RANSFORD, G. A., 1972. C o m m e n t s on t h e figure o f t h e Moon f r o m Apollo l a n d m a r k t r a c k i n g . The M o o n 5, 149-I57. Optical o b s e r v a t i o n s were m a d e f r o m t h e o r b i t i n g s p a c e c r a f t to c r a t e r s on t h e l u n a r surface d u r i n g Apollo missions 8, 10, 11, 12, 14, a n d 15. V e r y a c c u r a t e selenographic locations for 31 c r a t e r s h a v e b e e n o b t a i n e d f r o m t h e s e d a t a . The e s t i m a t e d radius values, w i t h r e s p e c t to t h e c e n t e r of m a s s of t h e Moon, for t h e n e a r side m a r i a were smaller t h a n t h e n o m i n a l l y a c c e p t e d value o f 1738km. Gross figures of t h e Moon e s t i m a t e s were o b t a i n e d for b o t h a sphere a n d a c o n s t r a i n e d ellipsoid. These d a t a a p p e a r to p r o v i d e some p r o o f t h a t t h e r e is a d i s p l a c e m e n t b e t w e e n t h e c e n t e r o f figure a n d t h e c e n t e r of m a s s o f t h e Moon. MOON--SURFACE FEATURES BEALS, C. S., 1972. L a v a filled craters a n d t h e t h e r m a l h i s t o r y of t h e l u n a r surface. N a t u r e 237, 226-227. I n o r d e r to e x p l a i n t h e v a r i e t y o f l a v a filled c r a t e r s it seems n e c e s s a r y to invoke a s e c o n d h e a t i n g o f t h e Moon, a possibility a l r e a d y s u g g e s t e d b y t h e age d e t e r m i n a t i o n s of h m a r materials. This p r o v i d e s t w o periods of l u n a r surface h e a t i n g a n d t h e r e f o r e t w o periods

d u r i n g w h i c h t h e cooled c r u s t is t h i n e n o u g h to m a k e l a v a filled c r a t e r s possible. I n o r d e r t o provide a semiquantitative test of the hypothesis o f two p e r i o d s o f h i g h surface t e m p e r a t u r e s e p a r a t e d b y a p e r i o d of cooling a n d t h i c k e n i n g crust, 8 l a v a filled c r a t e r s or l a v a c o v e r e d areas were e x a m i n e d using t h e n u m b e r o f small c r a t e r s 2 k m d i a m e t e r a n d over, p e r 104kin 2, as a n i n d i c a t i o n of relative age. The c r a t e r s fall into t w o d i s t i n c t groups, t h e inference is t h a t t h e s e t w o groups c o r r e s p o n d t o e v e n t s s e p a r a t e d b y a long i n t e r v a l of t i m e , a n d t h e d a t a are t h u s c o n s i s t e n t w i t h t h e general h i s t o r y p r e s e n t e d . EL-BAz, F., 1972. N e w geological findings in Apollo 15 l u n a r orbital p h o t o g r a p h y . Geochim. Cosmochim. Acta SuppL. 3, 1, 39 61. T h e p a n o r a mic a n d m e t r i c c a m e r a s y s t e m s , w h i c h were flown for t h e first t i m e on Apollo 15, o b t a i n e d a t o t a l o f 4140 p h o t o g r a p h s w i t h a resolution o f 1 - 3 m a n d 25 30m, r e s p e c t i v e l y . D a t a d e r i v e d f r o m t h e m e t r i c c a m e r a s y s t e m will allow m a p p i n g t h e overflown 12% o f t h e l u n a r surface a t 1:250 000 scale w i t h 5 0 m c o n t o u r s ; t h o s e o f t h e p a n o r a m i c c a m e r a will p r o d u c e large scale m a p s (up to l : 1 0 000) w i t h 5 10m contours. T h e H a s s e l b l a d c a m e r a was also utilized to o b t a i n oblique views w i t h color film. The combined data represent the most thorough p h o t o g r a p h i c coverage o f a n y Apollo m i s s i o n to d a t e . P h o t o g e o l o g i c i n t e r p r e t a t i o n o f t h e s e d a t a a n d correlation w i t h o t h e r r e m o t e l y s e n s e d d a t a , b o t h f r o m e a r t h a n d f r o m l u n a r orbit, will allow e x t r a p o l a t i o n o f k n o w l e d g e gained b y surface e x p l o r a t i o n t o large s e g m e n t s o f t h e m o o n . Several n e w f e a t u r e s o f p r o b a b l e volcanic origin were d e t e c t e d : (1) d a r k - h a l o e d cones in t h e Apollo I7 T a u r u s - L i t t r o w l a n d i n g site. These " c i n d e r c o n e s " m a y h a v e b r o u g h t to t h e surface p y r o e l a s t i c f r a g m e n t s f r o m d e e p w i t h i n t h e m o o n in t h e p o s t - m a r e p e r i o d of l u n a r surface h i s t o r y ; (2) a D - s h a p e d s t r u c t u r e w i t h lightcolored u n i t s a n d blister-like s m o o t h d o m e s in its floor. T h e s t r u c t u r e is b e l i e v e d to be a y o u n g collapsed e a l d e r a ; (3) w h a t a p p e a r s to be a l a v a lake on t h e l u n a r farside w i t h " l a v a m a r k s " and evidence of lava drainage into prominent fissures; (4) u n u s u a l l y large (up t o 4 0 k m in d i a m e t e r ) d o m e s n e a r R i m a S c h r o e d i n g e r I on t h e s o u t h e r n f a r s i d e ; a n d (5) n u m e r o u s l a v a flows in w e s t e r n Mare I m b r i u m , some o f w h i c h cross m a r e ridges. O t h e r f e a t u r e s on w h i c h n e w d a t a were o b t a i n e d i n c l u d e : (1) t w o l i n e a t e d u n i t s t h a t are i n t e r p r e t e d as landslides or rock a v a l a n c h e s ; one on t h e n o r t h w e s t e r n r i m o f T s i o l k o v s k y ( a p p r o x i m a t e l y 80kin long), a n d a smaller one ( a p p r o x i m a t e l y 5 k m long) in t h e T a u r u s - L i t t r o w site; (2) u n u s u a l light-colored swirls in Mare Inginii, Mare Marginis, a n d

MOON--SURFACE

O c e a n u s P r o c e l l a r u m . These sinuous m a r k i n g s m a y have been produced by alteration of the m a t e r i a l s a t t h e a n t i p o d a l areas of i m p a c t p o i n t s ; a n d (3) m a n - c a u s e d c h a n g e s in albedo, o b s e r v e d for t h e first t i m e f r o m l u n a r orbit, w h i c h i n c l u d e : b r i g h t e n i n g o f t h e surface area b e n e a t h t h e LM, p r o b a b l y due t o c o m p a c t i o n d u r i n g d e s c e n t ; a n d d a r k e n i n g o f t h e areas a r o u n d R o v e r a n d a s t r o n a u t foot t r a c k s , p r o b a b l y due to d e s t r u c t i o n of t h e (less t h a n 1 m m ) p h o t o m e t r i c layer. EL-BAZ, F., AND ROOSA, S.A., 1972. Significant r e s u l t s f r o m Apollo 14 l u n a r orbital p h o t o g r a p h y . Geochim. Cosmochim. Acta Suppl. 3, 1, 63-83. Apollo 14 o b t a i n e d 950 p h o t o g r a p h s f r o m l u n a r o r b i t using t h e H a s s e l b l a d a n d H y c o n c a m e r a s . T h e p h o t o g r a p h s reveal a n u m b e r o f n e w geologic f e a t u r e s as well as p r e v i o u s l y u n r e c o g n i z e d details of the morphology, structure, and s t r a t i g r a p h y o f l u n a r surface units. The p r i m a r y r e s u l t is t h e verification o f t h e e x t e n s i v e role o f v o l c a n i s m in t h e f o r m a t i o n a n d m o d i f i c a t i o n o f t h e l u n a r h i g h l a n d s , especially on t h e farside. T e r r a v o l c a n i s m a p p e a r s to be m a n i f e s t in t h e f o r m a t i o n o f (1) c o n s t r u c t i o n a l u n i t s of hilly a n d f u r r o w e d m a t e r i a l s o f regional e x t e n t as in t h e K a n t P l a t e a u in t h e c e n t r a l n e a r s i d e highlands and northwest of the crater Pasteur near t h e e a s t e r n l i m b o f t h e m o o n ; (2) s o m e w h a t viscous l a v a flows a n d pools a s s o c i a t e d w i t h f r a c t u r e s y s t e m s a n d / o r w h a t a p p e a r t o be volcanic c r a t e r s ; (3) craters, c r a t e r chains, a n d irregular depressions, p a r t i c u l a r l y on t h e l u n a r farside. T h e first p h o t o g r a p h s o f a flow channel, a l e v e e d sinuous rille t h a t a p p a r e n t l y o r i g i n a t e d b y l a v a flowage on t h e surface, were o b t a i n e d b y Apollo 14. A n o t h e r first is a h i g h resolution p h o t o g r a p h o f t h e i n t e r i o r of w h a t a p p e a r s to be t h e y o u n g e s t l u n a r c r a t e r y e t p h o t o g r a p h e d in t h e 2 0 - 4 0 k m size range. Also, p h o t o g r a p h i c s e q u e n c e s were m a d e a t zero p h a s e c o n d i t i o n s a n d a t low sun e l e v a t i o n angles, n e a r t h e t e r m i n a t o r . T h e l a t t e r c o n d i t i o n s are m o s t s u i t a b l e for s t u d y i n g small-scMe t o p o g r a p h i c v a r i a t i o n s o f l u n a r surface units. EL-BAZ, F., WORDEN, A. M., AND B~AND, V. D., 1972. A s t r o n a u t o b s e r v a t i o n s f r o m l u n a r o r b i t a n d t h e i r geologic significance. Geochim. Cosmochim. Acta Suppl. 3, 1, 85-104. To supplem e n t orbital p h o t o g r a p h y a n d o t h e r r e m o t e l y s e n s e d d a t a , visual o b s e r v a t i o n s were m a d e o f 15 l u n a r surface t a r g e t s d u r i n g Apollo mission 15. T h e 3 0 m resolving p o w e r o f t h e eye a n d its special sensitivities t o subtle differences in t e x t u r e a n d color-tone, w h e n c o u p l e d w i t h t h e interpretative powers of the brain provide a s y s t e m o f u n m a t c h e d q u a l i t y for l u n a r exploration. T h e e x t r a o r d i n a r y success of p e r f o r m i n g

FEATURES

81

t h e t a s k p r o v e s t h e o u t s t a n d i n g capabilities o f m a n a n d his use in spaceflight. A m o n g t h e significant results are (1) c h a r a c t e r i z a t i o n of t h e floor m a t e r i M o f T s i o l k o v s k y as no d a r k e r t h a n t h e a v e r a g e ( E r a t o s t h e n i a n ) m a r e material, a n d i n t e r p r e t a t i o n o f t h e l i n e a t e d u n i t on t h e c r a t e r r i m as a rock a v a l a n c h e ; (2) identification o f layers on t h e wall o f t h e c r a t e r P i c a r d , w h i c h is p r o b a b l y volcanic in origin, (3) e x p l a n a t i o n o f t h e r a y - e x c l u d e d zone o f t h e c r a t e r P r o c l u s as t h e result of s t r u c t u r a l l y controlled r a y s h a d o w ing; (4) o b s e r v a t i o n of cinder cones in t h e L i t t r o w area w i t h d a r k haloes t h a t p r o b a b l y are c o m p o s e d o f p y r o c l a s t i c d e p o s i t s ; a n d (5) recogn i t i o n t h a t t h e t e r m i n i o f n u m e r o u s sinuous rilles in Oceanus P r o c e l l a r u m are flooded w i t h younger mare materials that may have covered older t e r m i n a l deposits. CREELEY, R., AND HYDE, J . H., 1972. L a v a t u b e s o f t h e Cave Basalt, M o u n t St. Helens, W a s h i n g t o n . Geol. Soc. Amer. Bull. 83, 23972418. M a n y surface f e a t u r e s o f b a s a l t flows are d i r e c t l y r e l a t e d to lava t u b e s . P r e s s u r e w i t h i n t h e closed l a v a - t u b e s y s t e m c a u s e d b y outgassing a n d h y d r o s t a t i c p r e s s u r e a n d overflow o f lava f r o m r u p t u r e d r o o f sections (or f r o m c h a n n e l overflow prior to r o o f f o r m a t i o n ) result in f o r m a t i o n o f a t o p o g r a p h i c h i g h along m a n y sections of t h e l a v a - t u b e axis. I f r o o f r u p t u r e does n o t occur, t u m u l i m a y d e v e l o p in w e a k areas o f t h e roof, f o r m i n g p o s i t i v e f e a t u r e s (may be solid or hollow) 40 t o 5 0 m in d i a m e t e r a n d several m e t e r s high. Most of t h e hollow t u m u l i of t h e Cave B a s a l t collapsed, p r o b a b l y as a result o f w i t h d r a w a l o f s u p p o r t i n g l a v a d u r i n g d r a i n a g e of t h e l a v a tubes. R a i s e d - r i m c r a t e r s f o u n d in m a n y p a r t s o f t h e flow are a s s o c i a t e d w i t h lava t u b e s a n d were p r o b a b l y f o r m e d b y collapse o f hollow t u m u l i . HARTMANN, W. K . , 1972. P a l e o c r a t e r i n g o f t h e M o o n : R e v i e w o f p o s t - A p o l l o d a t a . Astrophys. Space Sci. 17, 48-64. As a result o f t h e d a t i n g o f l u n a r samples, we are in a p o s i t i o n t o utilize t h e l u n a r surface as a r e c o r d e r of environm e n t a l c o n d i t i o n s in t h e E a r t h - M o o n neighborh o o d in t h e p a s t . P l o t s o f c r a t e r d e n s i t y vs rock age a t different l u n a r l a n d i n g sites can be u s e d to d a t e u n e x p l o r e d l u n a r provinces. These p l o t s also d e m o n s t r a t e evolution in t h e p o p u l a t i o n of p l a n e t e s i m a l s t h a t s t r u c k t h e Moon. P r i o r to 4.1 aeons ago, t h e c r a t e r i n g r a t e on t h e Moon was a t least 103 t i m e s t h e p r e s e n t rate, a n d t h e r a t e d e c l i n e d w i t h a half-life less t h a n 8 × 10~yr. D u r i n g t h e i n t e r v a l f r o m 4.1 to 3.2 aeons ago, the n m n b e r ofplanetesimals showed an exponential d e c a y w i t h a half-life a b o u t 3 × 10Syr, c o r r e s p o n d i n g to s w e e p - u p o f particles f r o m solar orbits s o m e w h a t similar to t h o s e o f Apollo

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AFCRL B I B L I O G R A P I t Y - - 3 R D QUARTER 1972

asteroids. A m o r e n e a r l y c o n s t a n t c r a t e r i n g r a t e a p p l i e d in t h e last t h r e e aeons. These d a t a i n d i c a t e t h a t t h e Moon displays a t least t h e final stages o f a n a n c i e n t accretion process ; t h e y also set c e r t a i n c o n d i t i o n s on possible c a p t u r e processes r e l a t i n g to t h e M o o n ' s origin. PreApollo e x p e c t a t i o n s t h a t t h e Moon w o u l d p r o v i d e a " R o s e t t a S t o n e " for i n t e r p r e t i n g solar s y s t e m h i s t o r y a n d p l a n e t f o r m a t i o n t h u s a p p e a r justified. HOVCARD, i . D., 1972. E x p e r i m e n t a l studies on t h e f o r m a t i o n of l u n a r surface f e a t u r e s b y fluidization: Discussion. Geol. Soc. Amer. Bull. 83, 2195-2196. S c h u m m (1970) r e p o r t e d t h e results o f a series of e x p e r i m e n t s d e s i g n e d to s h o w t h a t some sinuous l u n a r rilles could h a v e f o r m e d as a result of fluidization of loose surface m a t e r i a l s by gases v e n t e d f r o m fractures. A l t h o u g h t h e r e are l u n a r analogs for some of t h e e x p e r i m e n t a l features, t h e a u t h o r ' s studies r e v e a l e d basic dissimilarities b e t w e e n t h e experim e n t a l f o r m s a n d m e a n d e r i n g rilles such as S c h r o e t e r ' s Rille. Thus, t h e e x p e r i m e n t a l rilles d i s p l a y e d scalloped sides in c o n t r a s t to t h e s m o o t h parallel sides of m a n y of t h e h m a r sinuous rilles; n o n e s h o w e d V - s h a p e d profiles or t a p e r e d e n d s as do m a n y l u n a r rilles; n o n e d i s p l a y e d s m o o t h l y c u r v i n g m e a n d e r s ; and, in s t r o n g c o n t r a s t t o m o s t sinuous l u n a r rilles, a h n o s t all h a d p r o n o u n c e d leveelike rims. E v e n m o r e i m p o r t a n t , h o w e v e r , is t h e unlikelihood t h a t t h e e x p e r i m e n t a l conditions r e q u i r e d to p r o d u c e t h e s i m u l a t e d m e a n d e r s w o u l d be d u p l i c a t e d in n a t u r e . I n a reply, S c h u m m s t a t e s t h a t a m a j o r difference b e t w e e n t h e m o d e l results a n d l u n a r rilles is t h e d e v e l o p m e n t of well-defined leveelike rims b o r d e r i n g t h e experim e n t a l fiuidization t r o u g h s . As H o w a r d observes, rims o f this t y p e do n o t a p p e a r t o b o r d e r l u n a r rilles. H o w e v e r , t h e Marius Hills rilles ( S c h u m m , 1970, Fig. 15) are flanked b y rims or levees, as p h o t o g r a m m e t r i c analysis o f L u n a r O r b i t e r 5 p h o t o g r a p h s b y t h e A r m y T o p o g r a p h i c Comm a n d h a s d e m o n s t r a t e d (Greeley, 1971 a, Fig. 5). :Nevertheless, t h e s e are n o t as s h a r p a n d well defined as t h e e x p e r i m e n t a l levees. H o w e v e r , u n d e r l u n a r c o n d i t i o n s a u n i t of gas will be 36 t i m e s m o r e effective t h a n u n d e r t e r r e s t r i a l conditions. Therefore, it is p r o b a b l e t h a t m a t e r i a l e j e c t e d f r o m a c r a t e r or t r o u g h b e i n g f o r m e d b y fluidization or o t h e r t y p e s of volcanic a c t i v i t y u n d e r l u n a r c o n d i t i o n s w o u l d be m o v e d a t relatively high velocities a n d w o u l d n o t necessarily be d e p o s i t e d on t h e edge of t h e f e a t u r e as a rim. HOWARD, K . A., HEAD, J . W., AND SWANN, G. A., 1972. Geology o f H a d l e y Rille. Geochim. Cosmochim. Acta S u p p l . 3, 1, 1-14. Apollo 15

d a t a s u p p o r t tile c o n c e p t t h a t H a d l e y Rille is a g i a n t collapsed lava t u b e t h a t o r i g i n a t e d a t its s o u t h end. The s o u t h h a l f of t h e rille is s i n u o u s a n d t h e b e n d s are n o t s t r u c t u r a l l y controlled, w h e r e a s t h e n o r t h h a l f o f t h e rille follows prem a r e s t r u c t u r a l t r o u g h s . Most of t h e rille has a V - s h a p e d profile a p p a r e n t l y f o r m e d b y recession of t h e rims a n d coalescence o f t a l u s from b o t h sides. T h e rille is scalloped a n d d i s c o n t i n u o u s locally, a n d t h e d e e p e s t p a r t s c o n s i s t e n t l y are t h e widest. This is a different r e l a t i o n s h i p f r o m t h a t s h o w n b y river chammls, b u t can i n s t e a d be e x p l a i n e d b y collapse, w i t h m o s t e x t e n s i v e f o u n d e r i n g a t t h e d e e p e s t points. The u p p e r 60m o f t h e walls of t h e rille at t h e Apollo 15 site expose several layers of m a r e basalt. Most are m a s s i v e u n i t s a v e r a g i n g a t least 10m t h i c k ; o t h e r s are layered. N u m e r o u s talus blocks d e r i v e d f r o m t h e m a s s i v e o u t c r o p s are 1 0 - 3 0 m across. Tile l u n a r flows are t h u s b o t h t h i c k a n d little j o i n t e d . The o u t c r o p ledge a n d blocky talus d e r i v e d f r o m it are a b s e n t w h e r e t h e rille a b u t s A p e n n i n e massifs, s h o w i n g t h a t t h e rille cuts t h r o u g h t h e m a r e basalt a n d a g a i n s t m a s s i f material. Several f e a t u r e s suggest t h a t t h e m a r e lavas s u b s i d e d differentially as m u c h as 100m a f t e r p a r t l y congealing. This could h a v e r e s u l t e d f r o m d r a i n k a g e i n t o a n d along a l a v a c o n d u i t t h a t b e c a m e H a d l e y Rille. HOWARD, K . A., OFFIELD, T. W., .AND WILSHIRE, H. a . , 1972. S t r u c t u r e of Sierra Madera, Texas, as a guide to c e n t r a l p e a k s of l u n a r craters. Geol. Soc. A m e r . Bull. 83, 27952808. Like h u n d r e d s o f o t h e r l u n a r c r a t e r s of p r o b a b l e i m p a c t origin, Copernicus c o n t a i n s c e n t r a l p e a k s p r e s u m e d to expose rocks u p l i f t e d f r o m b e n e a t h t h e c r a t e r floor. A possible analog o f t h e s e p e a k s on E a r t h is t h e central uplift of t h e Sierra M a d e r a e r y p t o e x p l o s i o n s t r u c t u r e , a p r o b a b l e i m p a c t scar (astrobleme) in s t r a t i f i e d P e r m i a n a n d Cretaceous rocks o f w e s t Texas. Analogy with experimental craters and with o t h e r c r y p t o e x p l o s i o n s t r u c t u r e s indicates t h a t t h e uplift a t Sierra M a d e r a p r o t r u d e d i n t o a c r a t e r (since d e s t r o y e d b y erosion) t h a t was a b o u t 12km across. I n a s m u c h as t h e rocks f o r m i n g such uplifts are d e r i v e d f r o m below t h e c r a t e r floors, analogous p e a k s in l u n a r c r a t e r s such as Copernicus m a y offer s a m p l e s o f l u n a r c r u s t u p l i f t e d f r o m d i s t a n c e s below t h e c r a t e r floor on t h e o r d e r o f o n e - t e n t h of t h e c r a t e r diameter. KOPaL, Z., 1972. Cosmic influences o f t h e early h i s t o r y o f t h e l u n a r surface. The M o o n 5, 200205. I t is p o i n t e d out t h a t t h e o b s e r v e d r a n d o m d i s t r i b u t i o n o f low-angle i m p a c t c r a t e r s over t h e l u n a r surface rules o u t t h e possibility t h a t particles initially responsible for t h e origin of

lV[OON--SURFACE LAYER such craters had, prior to impact, been in heliocentric orbits. The observed facts are more consistent with a view that paz~icles responsible for most of large primary impacts at the earliest stage of lunar history were moving with the E a r t h - M o o n gravitational dipole, and m a y have represented leftovers from the formation of this pair of cosmic bodies. The application of a similar argument to an equally obvious lack of directional effects in Martian cratering is, however, invalidated by a relatively large inclination of the Martian equator to the orbital plane of this planet. SUTTON, R. L., BAIT, M. H., AND SWANN, G. A., 1972. Geology of the Apollo 14 landing site. Geochim. Cosmochim. Acta Suppl. 3, 1, 27-38. Apollo 14 landed in the F r a Mauro region of the moon, within about l l 0 0 m of a 90m high ridge of the F r a Mauro formation, interpreted as being ejecta from the I m b r iu m Basin. The primary geologic objective of the mission was to sample ejecta from Cone Crater, which is 340m in diameter and penetrates at least 60m into the ridge. Data from the mission strongly support the Imbrian ejecta origin for the F r a Mauro formation. Returned samples and photographs show that ejecta from Cone Crater is composed of composite breecias that include multiple clasts of still older, pre-Imbrian, breccias. Cone Crater ejecta displays a wide range of thermal metamorphism effects. Samples from the valley where the Lunar Module landed, which was not on a recognizable ray of ejecta from Cone Crater, are predominantly fines and poorly consolidated breccias formed by the disintegration of Fra Mauro rocks, and probably are not volcanic rocks as had been postulated before the mission. MOON--SURFACE LAYER ADLER, I., TROMBKA, J., CTERAICD,J., LOWMAN, P., SCHMADEBECK, R., BLODGET, B., ELLER, E., WIN, L., LAMOTHE, R., OSSWALD, G., GORENSTEIN, 1)., BJORKI-IOLM, ])., GURSKY, H., AND HARRIS, B., 1972. Apollo 16 geochemical X - r ay fluorescence experiment: Preliminary report. Science 177, 256-259. The lunar surface was mapped with respect to magnesium, aluminum, and silicon as aluminum/silicon and magnesium/silicon intensity ratios along the projected ground tracks swept out by the orbiting Apollo 16 spacecraft. The results confirm the observations made during the Apollo 15 flight and provide new data for a number of features not covered before. The data are consistent with the idea that the moon has a widespread differentiated crust (the highlands). The aluminum/silicon and magnesium/silicon concentration ratios

83

correspond to those for anorthositic gabbros through gabbroic anorthosites or feldspathic basalts. The X ray results suggest the occurrence of this premare crust or material similar to it at the Descartes landing site. ANDERSON, A. W., BRAZIUNAS,T. F., JACOBY, J-., AND SMIT~, J . V., 1972. Thermal and mechanical history of breccias 14306, 14063, 14270, and 14321. Geochim. Cosmochim. Acta Suppl. 3, 1, 819-835. Breccia 14306 has three generations: I, light-gray basaltic (noritic) metabreccia; II, dark-gray polymict metabreccia; and I I I , medium-gray polymict host matrix. Type I fragments are partly glassy and have Mg-rich ilmcnite indicating recrystallization arrested at 850 to 1000°C. Type I I fragments contain abundant subrounded, weak to strongly shocked plagioclase clasts and minor variously shocked granitic rocks, coarsely-exsolved orthopyroxenes and round, rimmed rock fragments suggestive of ash flow transport of ejecta derived from plutonic and volcanic sources. Preservation of concentration gradients in rhyolite and devitrification of diaplectic plagioclase glass suggest brief annealing near 800°C. Type I I I matrix is crystal-rich with many contorted grains but is otherwise similar to II. Tentatively the authors regard I as Pre-Imbrian, and I I as the top of the Imbrian ejecta blanket (Fra Mauro formation). Type I I I possibly formed as I I was violently mixed with underlying crystal-rich material, possibly by impact while hot. Assuming ash flow transport without radiation loss, their data are consistent with initial impact heating amounting to 300°C or less, followed by heating during transport and deposition of less than 400°C, and a pre-impact temperature of the ejecta near or above 100°C. Av]~ LALLEMANT, H. G., AND CARTER, N. L., 1972. Deformation of silicates in some Fr a Mauro breecias. Geochim. Cosmochim. A cta Suppl. 3, 1, 895-906. A total of eighteen thin sections of Fra Mauro breccias have been studied in detail, using optical techniques, for evidence of static and dynamic deformational processes in the silicates. Microstructures due to shock deformation are similar to those found in silicates from Mare Tranquillitatis and Oceanus Procellarum, but commonly they appear to have been modified by high temperature annealing. Notable among annealed features are healed microfractures, planar arrays of cavities along pre-existing planar features (shock lamellae), and partial to total reerystallization of highly deformed olivines and clinopyroxenes. Lack of evidence for the orthopyroxene-clinopyroxene inversion also m ay indicate prolonged high temperature annealing. The annealing may have

84

AFCRL B I B L I O G R A P H Y - - 3 R D QUARTEI¢ 1972

t a k e n place a t d e p t h b y b u r i a l u n d e r a h o t ejecta blanket thrown out during the excavation of Mare I m b r i u m . T h e r e is n o u n e q u i v o c a l e v i d e n c e for a p p r e c i a b l e s t a t i c d e f o r m a t i o n in silicates f r o m F r a Mauro, in a c c o r d w i t h p r e v i o u s r e s u l t s for Mare T r a n q u i l l i t a t i s a n d O c e a n u s P r o c e l l a r u m . T h u s it a p p e a r s as if a t least t h e o u t e r l a y e r of t h e m o o n a t t h e s e t h r e e sites h a s not undergone substantial tectonic activity since c r y s t a l l i z a t i o n ca, 3 to 4 billion y e a r s ago. BELL, P. M., AZ~D MAO, H . K., 1972. Crystalfield effects of iron a n d t i t a n i u m in selected g r a i n s of Apollo 12, 14, a n d 15 rocks, glasses, a n d fine fractions. Geochim. Cosmochim. A cta Suppl. 3, 1, 545-553. P o l a r i z e d crystal-field a b s o r p t i o n b a n d s in t h e n e a r i n f r a r e d c a u s e d b y iron a n d t i t a n i u m i n d i c a t e t h e i r a t o m i c site c o o r d i n a t i o n and oxidation state m lunar pyroxenes and olivines f r o m s a m p l e s 12040,18, 12040,49, 12063,79, 14306,6, a n d 15601,94. T h e energies of t h e crystal-field t r a n s i t i o n s , a n d t h e r e s u l t i n g b a n d s , s h i f t w i t h c o n c e n t r a t i o n . I n l u n a r glasses f r o m s a m p l e s 14163,33 a n d 15601,94, a n e a r i n f r a r e d b a n d c a u s e d b y ferrous iron shifts o n l y in i n t e n s i t y w i t h c o n c e n t r a t i o n . I n t e r a c t i o n of t h i s b a n d w i t h p a r t of a s t r o n g a b s o r p t i o n in t h e u l t r a v i o l e t f r o m t i t a n i u m causes t h e colors of t h e s e glasses. T h e visible " w i n d o w " , a m i n i m u m b e t w e e n t h e iron a n d t i t a n i u m a b s o r p t i o n s , shifts as a f u n c t i o n of t h e t o t a l c o n c e n t r a t i o n of t i t a n i u m a n d of t h e r a t i o of t r i v a l e n t to q u a d r i v a l e n t t i t a n i u m . T h e cons t a n c y of e n e r g y of t h e iron a b s o r p t i o n in l u n a r glasses implies t h e following: (a) T h e s t r u c t u r a l s y m m e t r y of t h e a t o m i c site of iron in l u n a r glasses is i n d e p e n d e n t of b u l k c o m p o s i t i o n . (b) T h e t h e r m a l r a d i a t i v e p r o p e r t i e s of l u n a r soils c o m p o s e d p r i m a r i l y of l u n a r glass are r e m a r k a b l y u n i f o r m . (e) S p e c t r a of soils composed of glass m e a s u r e d on t h e l u n a r surface s h o u l d include v a l u e s of t h e a m p l i t u d e as well as w a v e l e n g t h of a b s o r p t i o n if t h e y are t o b e u s e d to e s t i m a t e t h e iron c o n t e n t . BENCE, A. E., AND I:)APIKE, J . J . , 1972. P y r o x e n e s as recorders of l u n a r b a s a l t petrogenesis: Chemical t r e n d s d u e to c r y s t a l - l i q u i d i n t e r a c t i o n . Geochira. Cosmochim. Acta Suppl. 3, 1, 431-469. P y r o x e n e s f r o m b a s a l t s collected o n t h e Apollo 11, 12, 14, 15, a n d L u n a 16 missions h a v e e x p e r i e n c e d a diverse r a n g e of crystallizat i o n histories as i n d i c a t e d b y t h e i r chemical, c r y s t a l l o g r a p h i c , mo~lohological, a n d p a r a g e n e t i c r e l a t i o n s h i p s . A l t h o u g h t h e final stages of l u n a r b a s a l t c r y s t a l l i z a t i o n a p p e a r to b e r a p i d nearsurface events, t h e initial stages v a r y cons i d e r a b l y a m o n g t h e different b a s a l t types. Differences in b a s a l t b u l k r o c k compositions,

e m p l a c e m e n t histories, a n d i n t e n s i v e p a r a m e t e r s (T, P , fo2) are r e c o r d e d i n t h e p a r a g e n e t i c s e q u e n c e of t h e b a s a l t c r y s t a l l i z a t i o n , a n d t h e pyroxene-crystallization trends on the quadrilateral, Ti/A1 plots, T i - C r - A 1 plots, T i - C r - A I v' plots, a n d A1/Si v e r s u s F e / M g plots. F o u r b r o a d t y p e s of b a s a l t s c a n b e d i f f e r e n t i a t e d on t h e b a s i s of t h e i r p y r o x e n e c h e m i c a l t r e n d s a n d t e x t u r e s . B a s a l t s w i t h h i g h TiO2/A1203 ratios, r e l a t i v e l y e a r l y c r y s t a l l i z a t i o n of plagioclase, one-stage, n e a r - s u r f a c e c r y s t a l l i z a t i o n , a n d fo2 - 1 0 - 1 3 a t m a t 1000°C (Apollo 11, L u n a 16, 12022) h a v e p y r o x e n e s w i t h Ti/A1 (atomic) _ ½, a c o n t i n u o u s c r y s t a l l i z a t i o n t r e n d on t h e p y r o x e n e q u a d r i lateral, c o m p o s i t i o n s on or n e a r t h e Ti Cr join in t h e t e r n a r y p l o t Ti Cr-A1 v[, a n d A1/Si v e r s u s F e / M g t r e n d s s h o w i n g a s h a r p decrease in A1/Si a t low F e / M g followed b y a m o r e g r a d u a l d e c r e a s e a t h i g h e r F e / M g ratios. P y r o x e n e s f r o m b a s a l t s w i t h lower TiO2/A1203 ratios, d e l a y e d plagioclase c r y s t a l l i z a t i o n , a n d a t w o - s t a g e h i s t o r y show s h a r p b r e a k s in t h e c r y s t a l l i z a t i o n t r e n d s o n t h e q u a d r i l a t e r a l , a n d o n t h e Ti/A1, T i - C r A1 vl, A1/Si v e r s u s F e / M g d i a g r a m s w h e n plagioclase s t a r t s t o crystallize. B a s a l t s of essentially t h e s a m e c o m p o s i t i o n b u t low f % ( ~ 1 0 - 1 6 a t m a t 1000°C) show a m a r k e d difference o n t h e Ti/A1 plot w i t h l a t e - s t a g e p y r o x e n e s a p p r o a c h i n g Ti/A1 = 1, w h i c h t h e a u t h o r s i n t e r p r e t as a d d i t i o n of c o m p o n e n t R2+Ti3+SiA10~,. H i g h a l u m i n a b a s a l t s w i t h early c r y s t a l l i z a t i o n of plagioclase a n d a o n e . s t a g e n e a r - s u r f a c e h i s t o r y show significant A1v' e n r i c h m e n t in t h e e a r l y p y r o x e n c s ( o r t h o p y r o x e n e s ) a n d Ti/A1 r a t i o s a p p r o a c h i n g ½in t h e late stages (clinopyroxenes). BROWN, G. M., EMELEUS, C. H., HOLLAND, J. G., 1;)ECKETT, A., AND PHILLIPS, ]:~., 1972. M i n e r a l - c h e m i c a l v a r i a t i o n s in Apollo 14 a n d Apollo 15 b a s a l t s a n d g r a n i t i c fractions. Geochim. Cosmochim. Acta Suppl. 3, l , 141-157. F e l d s p a r - p h y r i c b a s a l t s from t h e F r a M a u r o f o r m a t i o n p r o b a b l y are plagioclase c u m u l a t e s f r o m a b a s a l t rich in K R E E P - t y p e c o m p o n e n t s . T h e residual p h a s e s are rhyolitic glass a n d m i n e r a l s rich in K, B a , R E E , Zr, a n d P, s i m i l a r to t h o s e in Apollo l l , 12 a n d 15 basalts. T h e p y r o x e n e s are z o n e d f r o m m a g n e s i a n o r t h o p y r o x e n e cores to p y r o x f e r r o i t e rims, a n d A I : T i values i n d i c a t e initial c r y s t a l l i z a t i o n in e q u i l i b r i u m w i t h plagioclase. Calcic g r o u n d m a s s plagioclase c o m p o s i t i o n s r e l a t i v e to p h e n o c r y s t s i n d i c a t e some loss of N a d u r i n g l a t e - s t a g e c r y s t a l l i z a t i o n . T h e four Apollo 15 b a s a l t s a m p l e s show t h r e e b r o a d l y c o n t r a s t e d p y r o x e n e t r e n d s , suggestive of f o r m a t i o n in t h r e e l a v a flows w i t h different cooling rates. A I : T i values r a n g e f r o m 7:1 to l½:1 in z o n e d crystals, t h e r i m s p r o b a b l y c o n t a i n i n g Ti 3+. Apollo 14 breccias c o n t a i n

MOON--SURFACE LAYER fairly a b u n d a n t patches of rhyolite, of granop h y r e p a r t l y m e l t e d to rhyolite, and of troctolite (An95, Foss) w i t h harrisitic c u m u l a t e t e x t u r e . T h i s suggests high-level crystal fractionation, v e r y early in t h e m o o n ' s history, to yield a granitic crustal differentiate. N e w analyses of t r a n q u i l l i t y i t e s in basalt and g r a n o p h y r e (Apollo 14 and 15) and of two new zirkelite-type minerals (one w i t h 22.5% Y203 + RE2Oa) , suggest t h a t increases in Y, Zr, N b (as well as Rb, K and Ba) from the Apollo 11 t h r o u g h 12 to 14 soils could be associated w i t h an increasing granitic component. As K R E E P basalt compositions cannot be derived from addition of granite to basalt (or norite), t h e granite p r o b a b l y is a differentiate of a n c i e n t K R E E P basalt (Meyer, 1972). Whitlockires range widely in R E 2 0 3 and M g O : F e O ratios, and one crystal (Apollo 15 basalt) contains 1% SrO and the usual n e g a t i v e E u a n o m a l y . Variable c o n t a m i n a t i o n of mare basalts by granite-bearing phases (K-feldspar or Sr-whitlockite) could, therefore, produce anomalies in the R b - S r systematics. BuNcI~, T. E., KEIL, K., AND PRINZ, M., 1972. Mineralogy, petrology and chemistry of lunar rock 12039. Meteoritics 7, 245-255. R o c k 12039 belongs to the olivine-depleted group of magm a t i c rocks characterized by n o r m a t i v e and m o d a l SIC2, absence or v e r y low a b u n d a n c e of olivine, and high F e O / ( F e O + MgO), Ti/Cr, and CaO/MgO ratios. Clinopyroxenes in this rock show a complex, essentially continuous, compositional zonation from augite cores t h r o u g h ferroaugite to ferrohedenbergite with an a b r u p t discontinuity at the pyroxferroite c o n t a c t and, thus, are different from p y r o x e n e in most other Apollo 12 rocks. Two grains contain t h i n subcalcic pigeonite zones. T e x t u r e , presence of v e r y fine (<1/,m) exsolution lamallae, and p y r o x e n e zoning indicate a relatively rapid cooling history a n d pronounced i n situ chemical fractionation. R o c k 12039, on t h e basis of mineralogy and bulk composition, is t h e most highly differentiated m e m b e r of the olivine-depleted basalt group. BUNCH, T. E., QUAIDE, W., ~:)RINZ, M., KEIL, K., AND DOWT¥, E., 1972. L u n a r u l t r a m a tic glasses, chondrules and rocks. N a t u r e 239, 57 59. Compositional d a t a and t e x t u r e s of Apollo 15 green glass rocks and mierobreccias indicate t h a t these rocks m o s t likely formed in thick layers of i m p a c t - p r o d u c e d and modified material. Such deposits m u s t be t h e products of v e r y large events, possibly the I m b r i u m impact, suggesting t h a t the Apollo 15 ultramafic glasses and possibly green glasses from other sites were d e r i v e d from p r e - I m b r i u m ultramafic rocks. I f this conclusion is correct, t h e n t h e age of green glasses would precisely date the I m b r i u m basin

85

formation. Alternatively, the occurrence of ultramafic rocks at the Apollo 12 site w i t h compositions similar to the green glass m a y indicate t h a t rocks of green glass composition m a y exist at various places on the Moon; for example, in t h e lower levels of basins filled by lava. F u r t h e r m o r e , green glasses from all mission sites m a y h a v e originated by a similar m e c h a n i s m and m a y not be p a r t of t h e I m b r i u m basin ejecta but r a t h e r m a y be later deposits of ejecta e x c a v a t e d b y p o s t - I m b r i u m impacts which p e n e t r a t e d primitive, early basin filling flows. W h a t e v e r their origin, t h e widespread occurrence of ultramafic glasses in l u n a r samples and of similar rocks indicates t h a t ultramafic rocks are an i m p o r t a n t c o m p o n e n t of the l u n a r crust. BURNS, R. G., ABu-EID, R. M., AND HUGGINS, ]?. E., 1972. Crystal field spectra of l u n a r pyroxenes. Geochim. Cosmochim. Acta S u p p l . 3, 1, 533-543. Absorption spectra in t h e visible and near infrared regions h a v e been o b t a i n e d for p y r o x e n e single crystals in rocks from t h e Apollo 11, 12, 14, and 15 missions. The polarized spectra are compared w i t h those obtained from terrestrial calcic clinopyroxenes, subcalcic augites, pigeonites, and orthopyroxenes. The l u n a r pyroxcnes contain several broad, intense absorption bands in the near infrared, t h e positions of which are related to bulk composition, F e 2+ site occupancy and s t r u c t u r e - t y p e of the pyroxene. The visible spectra contain several sharp, weak peaks m a i n l y due to spinforbidden transitions in Fe 2+. Additional weak bands in this region in Apollo I 1 p y r o x e n e s are a t t r i b u t e d to Ti 3+ ions. Spectral features from Fe 3+, Mn 2+, Cr 3+, and Cr z+ were not observed. The spectral evidence for Ti 3+ ions suggests t h a t cation substitution in the l u n a r pyroxenes m a y be more complex t h a n t h e R.oc 2+t -F 2Sit*+ -4++ 2Alta+ coupled substitution m e c h a n i s m Wloct suggested previously. BUSCIIE, F. D., PRINZ, M., KEIL, K., AND KURAT, G., 1972. L u n a r zirkelite: A u r a n i u m bearing phase. E a r t h Planet. Sci. Lett. 14, 313-321. Zirkelite (simplified CaZrTiOs) containing 7 - 1 7 w t % oxides of t r i v a l e n t elements (largely y t t r i u m and the rare earths) and m i n o r a m o u n t s of U, Th, and P b is described from an Apollo 12 feldspathie peridotite (12036,9) and two K R E E P - t y p e norite lithic fragments sepa r a t e d from Apollo 14 loose fines (14163,39 and 14257,3). Q u a n t i t a t i v e electron microprobe analyses indicate t h a t this lunar phase conforms more closely to the zirkelite formula (generalized A2+B~+Os) t h a n to the zirconolite formula (generalized A2+B~+OT). BUTLER, P., JR., 1972. Compositional charac-

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AFCRL BIBLIOGRAPHY--3RD QUARTER 1972

teristics o f olivines f r o m Apollo 12 samples. Geochim. Cosmochim. A c t a 36, 773 785. The olivine p h e n o c r y s t s o f four b a s a l t s (12004, 12008, 12009 a n d 12022) are c o n c e n t r i c a l l y z o n e d a n d h a v e core c o m p o s i t i o n s a b o u t as m a g n e s i a n as e x p e r i m e n t a l l y p r o d u c e d liquidus olivines, f e a t u r e s w h i c h suggest fractional c r y s t a l l i z a t i o n a n d a b s e n c e of F e Mg requilibration. I n t h e m a g n e s i u m - a n d olivine-rich g r a n u l a r basalt 12035, t h e olivines are e i t h e r u n z o n e d or are z o n e d t o w a r d a d j a c e n t grains a n d h a v e c o m p o s i t i o n s m o r e iron-rich t h a n e i t h e r c u m u l u s olivines or liquidus olivines (should t h e rock r e p r e s e n t t h e c o m p o s i t i o n of a melt), f e a t u r e s w h i c h suggest e x t e n s i v e F e - M g re-equilibration. I f one a s s u m e s t h a t c o n c e n t r a tions o f m i n o r e l e m e n t s a t c r y s t a l l i z a t i o n h a v e also b e e n p r e s e r v e d in t h e Mg-rich c e n t e r s of olivines in tim b a s a l t p o r p h y r i e s , identification o f two possible c o m a g m a t i c pairs can be m a d e : 12004 a n d 12009 (lower Ti a n d higher Cr in olivines), a n d 12008 a n d 12022 (higher Ti a n d lower Cr in olivines). Correlations are o b s e r v e d b e t w e e n t h e F e - M g p r o p o r t i o n s a n d t h e conc e n t r a t i o n s of m i n o r e l e m e n t s in olivine (Ti, Mn a n d Ca all follow Fe, Cr follows Mg). CARR, M. H., AND MEYER, C. E., 1972. Chemical a n d p e t r o g r a p h i c c h a r a c t e r i z a t i o n of F r a Mauro soils. Geochim. Cosmochim. A c t a S u p p l . 3, l , 1015-1027. The 70-1000/xm size f r a c t i o n s of six regolith s a m p l e s f r o m t h e Apollo 14 site were c h a r a c t e r i z e d its t e r m s o f t h e i r c o m p o n e n t s . Glass f r a g m e n t s are m o s t c o m m o n (50 82%), being e i t h e r a t r a n s p a r e n t h o m o geneous glass or d a r k cloudy glass l a d e n w i t h m i n e r a l debris. M e t a breccia f r a g m e n t s cons t i t u t e 1 7 - 1 8 % of t h e samples a n d t w o t y p e s are recognized, d a r k m e t a b r e c c i a s , m o s t c o m m o n in s a m p l e s close to Cone Crater rays, a n d light m e t a b r e e c i a f r a g m e n t s , w h i c h g r e a t l y pred o m i n a t e elsewhere. 0.6 6 % of t h e f r a g m e n t s are igneous rock, 4 14% are m i n e r a l grains. Most o f t h e glasses a n d all t h e m e t a b r e c c i a f r a g m e n t s a p p e a r to be d e r i v e d locally a n d c o m p o s i t i o n a l l y are similar to p r e v i o u s l y d e s c r i b e d K R E E P n m t e r i a h Their relative p r o p o r t i o n s are cons i s t e n t w i t h d e r i v a t i o n f r o m a rock s e q u e n c e in w h i c h light m e t a b r e c c i a s are m o r e c o m m o n close to t h e surface a n d d a r k m e t a b r e c c i a s are m o r e c o m m o n a t g r e a t e r d e p t h s . I n c l u d e d also are exotic c o m p o n e n t s f r o m t w o m a i n sources, the nearby mare and a unit with the composition o f f e l d s p a t h i c basalt, possibly t h e Cayley formation. CARTER, J. L., AND McKA'~~, D. S., 1972. Metallic m o u n d s p r o d u c e d b y r e d u c t i o n o f m a t e r i a l of s i m u l a t e d l u n a r c o m p o s i t i o n a n d implications on t h e origin o f metallic m o u n d s on

h m a r glasses. Geochim. Cosmochim. A eta S u p p l . 3, 1, 953 970. Silicate glass of c o m p o s i t i o n similar t o b r o w n l u n a r glass was r e d u c e d w i t h c a r b o n a n d h y d r o g e n . The t y p i c a l c o m p l e x iron sulfide a n d metallic iron m o u n d f o r m e d b y r e d u c t i o n w i t h c a r b o n is zoned. I t s i n t e r i o r is metallic iron or a m i x t u r e o f iron sulfide a n d metallic iron. The o u t e r layer is p u r e metallic iron w h i c h is generally d i s c o n t i n u o u s , b u t t h e surface of t h e m o u n d n e x t to t h e silicate h o s t is iron sulfide. This t y p e o f m o u n d c o m m o n l y has a w a i s t o f metallic iron a n d a void b e n e a t h it. The silicate surface of t h e void is c o v e r e d w i t h d r o p l e t s or stringers of iron sulfide. The c o m p l e x iron sulfide a n d metallic iron m o u n d s f o r m e d b y r e d u c t i o n w i t h h y d r o g e n generally are zoned. Tile o u t e r layer is iron sulfide or a m i x t u r e o f iron sulfide a n d metallic iron, b u t t h e i n t e r i o r is metallic iron a n d iron sulfide, a n d t h e m o u n d m a t e r i a l n e x t to t h e silicate h o s t is iron sulfide. On t h e surface o f some c o m p l e x m o u n d s , globules o f silicate m a t e r i a l are p r e s e n t . I n one e x a m p l e , t h e globules consist o f particles o f a h n n i n n m oxide s u r r o u n d e d b y silicate material. I n t u r n , t h e m a r g i n of t h e globules is s u r r o u n d e d b y iron s u l f d e . D i m p l e s are p r e s e n t a n d t h e surface o f t h e d i m p l e s is c o v e r e d b y d e n d r i t i c s h e a t h s o f iron sulfide a n d isolated metallic iron globules. These d a t a suggest t h a t : (I) t h e ratio o f sulfur to iron has direct b e a r i n g on t h e m o r p h o h ) g y o f metallic m o u n d s ; (2) t h e g r o w t h t i m e also influences t h e n a t u r e o f metallic m o u n d s ; a n d (3) m o u n d s p r o d u c e d b y r e d u c t i o n w i t h cart)on are different f r o m m o u n d s p r o d u c e d bv r e d u c t i o n w i t h h y d r o g e n . The l a b o r a t o r y d a t a suggest, t h a t m o s t metallic m o u n d s on h m a r glasses did n o t f o r m b y r e d u c i n g process in situ. t t o w e v e r , d u r i n g t h e m e l t i n g o f l u n a r soil, for e x a m p l e during a meteoroid impact event, hydrogen and to a lesser e x t e n t carbon, as a result of t r a p p e d solar winds, m a y p l a y a t least a s e c o n d a r y role in t h e f o r m a t i o n of metallic iron, a n d m a y be responsible in a large p a r t for t h e f o r m a t i o n o f m o u n d s t h a t are low its nickel w h i c h c o m m o n l y occur in t r a i n s or p a t t e r n s on t h e g l a s s - b o n d e d agglutinates. I n addition, it is inferred f r o m t h e s e d a t a t h a t t h e iron m o u n d s rich its nickel, cobalt, sulfur, a n d p h o s p h o r u s m a y be remobilized c o m p o n e n t s of m e t e o r i t e s a n d proba b l y f o r m e d in t h e i m p a c t - g e n e r a t e d d e b r i s cloud.

CAVARRETTA, G., CORADINI, A., FUNICIELLO, R., FULCHIGNONI, M., TADDEUCCI, i . , AND TItIGILA, R., 1972. Glassy particles in Apollo 14 soil 14163,88: Peculiarities a n d genetic considerations. Geochim. Cosmochim. Acta S u p p l . 3, 1, 1085 1094. Glassy particles w i t h well-defined m o r p h o l o g i e s h a v e been s t u d i e d in t h e fractiou

MOON--SURfACE LAYE~ g r e a t e r t h a n 621zm f r o m Apollo soil 14163,88. Besides spheres a n d s p h e r e - d e r i v e d forms, t h e authors have considered the "ropy strands glasses." T h e y a p p e a r to c o m p r i s e a welldefined c h e m i c a l g r o u p clearly different f r o m o t h e r l u n a r glasses. T h e mafic e l e m e n t s are constant, whereas potassium and phosphorus show a wide r a n g e of s y m p a t h e t i c v a r i a t i o n , s u g g e s t i n g a v a r i a b l e c o n t e n t of t h e K R E E P c o m p o n e n t . T h e p r o b a b l e genetic process prod u c i n g t h e r o p y glasses a n d t h e i r c o a t i n g h a s b e e n i n v e s t i g a t e d in t e r m s of tile e n e r g y distrib u t i o n b e t w e e n projectile a n d t a r g e t d u r i n g a n i m p a c t e v e n t . T h e c o a t i n g o n t h e r o p y glasses is c a u s e d b y t h e w e l d i n g of small, still fluid particles o n t h e m a i n b o d y w i t h i n a long-lived p h n n e t h a t is g e n e r a t e d d u r i n g a c a t a s t r o p h i c e v e n t i n v o l v i n g energies g r e a t e r t h a n 1O2°ergs. CHAP, E. C. T., BEST, J . B., AND MINKIN, J . A., 1972. Apollo 14 glasses of i m p a c t origin a n d t h e i r p a r e n t rock types. Geochim. Cosmochim. Acta Suppl. 3, 1, 907-925. T h e color, r e f r a c t i v e indices (R.I.), a n d c h e m i c a l c o m p o s i t i o n h a v e b e e n d e t e r m i n e d for m o r e t h a n 200 Apollo 14 glass particles of i m p a c t origin f r o m t h e fines a n d breccias. As was f o u n d for Apollo 11 a n d 12, t h e Apollo 14 glasses fall i n t o d i s t i n c t c h e m i c a l g r o u p s w i t h c h a r a c t e r i s t i c colors a n d R . I . ranges. T h e a u t h o r s i n t e r p r e t t h e s e c h e m i c a l g r o u p s as r e p r e s e n t i n g specific p a r e n t rock types. T h e y m a y he fused fines or breceias, f u s e d u n c o n t a m i n a t e d or c o n t a m i n a t e d igneous rocks, or fused m e t a m o r p h i c rocks. F r o m t h e e x a m i n a t i o n of p l o t s of r e f r a c t i v e indices, c h e m i c a l v a r i a t i o n s , a n d C I P W n o r m s , t h e y find t h a t t h e r e are a t least e i g h t d i s t i n c t c h e m i c a l g r o u p s of Apollo 14 rock glasses of i m p a c t origin. ( T h e t o m o r p h i c plagioclase glass p r o d u c e d b y s h o c k is p r e s e n t in Apollo 14 s a m p l e s b u t is n o t c o n s i d e r e d in t h i s paper.) T h e m o s t a b u n d a n t group, w i t h a c o m p o s i t i o n a l r a n g e o v e r l a p p i n g t h a t of t h e Apollo 14 fines a n d r e g o l i t h microbreccias, is similar t o h o r n f e l s e d n o r i t i c m i c r o breccias or m i c r o n o r i t e h o r n f e l s in c o m p o s i t i o n . O n l y one d i s t i n c t group, w i t h a n a n o r t h o s i t i c g a b b r o c o m p o s i t i o n , also is p r e s e n t a m o n g Apollo 11 a n d 12 fines. T h e o t h e r p a r e n t r o c k t y p e s i n d i c a t e d b y o u r s t u d y include r o c k s of a n o r t h o s i t i c , f e l d s p a t h i c p e r i d o t i t e , troctolitic, m a r e b a s a l t , a n d p e r i d o t i t e c o m p o s i t i o n s . Glasses of salic c o m p o s i t i o n also are p r e s e n t b u t are v e r y rare. A m a j o r conclusion f r o m t h i s s t u d y is t h a t t h e d o m i n a n t p a r e n t r o c k t y p e of t h e Apollo 14 h i g h l a n d site is similar i n c o m p o s i t i o n to a n n e a l e d n o r i t i c rocks r a t h e r t h a n a n o r t h o s i t e . CHAO, E. C. T., MINKIN, J. A., AND BEST, J . B., 1972. Apollo 14 breccias : G e n e r a l c h a r a c t e r i s t i c s a n d classification. Geochim. Cosmochim. Acta

87

Suppl. 3, 1 , 6 4 5 - 6 5 9 . T h e Apollo 14 breccias are c o m p l e x a n d arc c h a r a c t e r i z e d b y a wide r a n g e of clast t y p e s a n d t e x t u r e s . T h e p r i n c i p a l f r a g m e n t t y p e s in t h e breccias are (1) h o r n f e l s e d n o r i t i c m i c r o b r e c c i a s ; (2) m i c r o n o r i t e h o r n f e l s ; (3) d c v i t r i f i e d glass; a n d (4) o p h i t i c a n d o t h e r k i n d s of b a s a l t . D a r k v i t r o p h y r i c f r a g m e n t s , f i n e - g r a i n e d a n o r t h o s i t i c rocks a n d a n o r t h o s i t i c breccias, olivine-rich rocks, p y r o x e n e - r i c h fragm e n t s , a n d breccias w i t h inclusions of earlier breccias are also p r e s e n t , b u t t h e y are comp a r a t i v e l y rare. B a s e d on f r a g m e n t p o p u l a t i o n , n a t u r e of t h e m a t r i x , g r a i n size a n d p o r o s i t y , m e t a m o r p h i c h i s t o r y , a n d b u l k c h e m i c a l composition, t h e Apollo 14 breccias c a n h e classified chiefly i n t o r c g o l i t b microbreccias, F r a M a u r o brcccias a n d s p h e r u l e - r i c h microbreccias. F u r t h e r s u b d i v i s i o n s are b a s e d p r i n c i p a l l y o n t h e i n t e r p r e t a t i o n of i n e t a m o r p h i c h i s t o r y . T w e n t y - s i x Apollo 14 breccias h a v e b e e n so classified. Tlle c o m p l e x f r a g m e n t t y p e s c o n t a i n e d in Apollo 14 breecias r e p r e s e n t m u l t i p l e episodes of h e a t i n g a n d f r a g m e n t a t i o n . T h e y p r o b a b l y are preI m b r i a n a n d were n o t p r o d u c e d b y t h e i m p a c t effects of a single e v e n t . T h e v a r i a b i l i t y of t h e i r f r a g m e n t p o p u l a t i o n s is i m p o r t a n t in t h e interp r e t a t i o n of p r e - I m b r i a n geologic h i s t o r y . CItRISTOPHE-MICHEL-LEvY, M., LEVY, C., CAYE, R., AND PIERROT, R., 1972. The magnesian s p i n e l - b e a r i n g rocks f r o m t h e F r a M a u r o f o r m a t i o n . Geochim. Cosmochim. Acta Suppl. 3, 1, 887-894. T h e m a g n e s i u m spinels f o u n d in m a n y F r a M a u r o breccias are slightly c h r o m i ferous pleonastes. They are particularly a b u n d a n t in breccia 14063. T h i s m i n e r a l , in isolated f r a g m e n t s , is one of t h e p r o d u c t s of b r e c c i a t i o n of v a r i o u s rocks, m o s t l y a n o r t h ositic, w h i c h are p r e s e n t as clasts in t h e breccia. I t also is f o u n d as e u h e d r a l c r y s t a l l i t e s in glassy debris. T h e large n u m b e r of s p i n e l - b e a r i n g rock t y p e s p r o b a b l y is i n d i c a t i v e of a s e q u e n c e of h y p e r a l u m i n o u s rocks n o t o b s e r v e d in tile m a r e regions. This s e q u e n c e c o u l d b e c h a r a c t e r i s t i c of t h e s u b s t r a t u m , b r o u g h t to t h e surface b y t h e Cone C r a t e r i m p a c t e v e n t . CZANK, M., GIRGIS, K., I-IARNIK, A. B., LAVES, F., SCHMID, R.~ SCttULZ, H., AND WEBER, L., 1972. C r y s t a l l o g r a p h i c s t u d i e s of l u n a r plagioclases from samples 14053, 14163, 14301, a n d 14310. Geochim. Cosmochim. Acta Suppl. 3, 1, 603-613. T h e a u t h o r s s t u d i e d plagioelases f r o m Apollo 14 b a s a l t s , fines, a n d a breccia. T h e s a m p l e s h a v e b e e n i n v e s t i g a t e d optically, b y m i c r o p r o b e , a n d X r a y precession m e t h o d s . T h e c h e m i c a l c o m p o s i t i o n of t h e c r y s t a l s i n v e s t i g a t e d b y X r a y s lies b e t w e e n A n 75 a n d A n 95. B a s a l t i c plagioclases predominantly have An contents between 85%

88

AFCRL BIBLIOGRAPHY--3RD QUARTER 1972

a n d 9 4 % in t h e w e a k l y z o n e d cores, w h e r e a s t h e A n c o n t e n t s of four breccia c r y s t a l s r a n g e in a n i n t e r v a l of 7 6 % to 9 3 % . Small zones of h i g h p o t a s s i u m c o n c e n t r a t i o n s h a v e b e e n d e t e c t e d in these m a r g i n s . Most plagioclase c r y s t a l s are intimately twinned. The authors optically o b s e r v e d in d e c r e a s i n g o r d e r of f r e q u e n c y albite, c a r l s b a d , a l b i t e - c a r l s b a d , pericline, a n d b a v e n o twins. T h e v o l u m e r a t i o s of t h e different t w i n i n d i v i d u a l s p r e s e n t in single c r y s t a l s were d e t e r m i n e d b o t h o p t i c a l l y a n d b y X rays. Discrepancies were n o t e d b e t w e e n t h e results found by these two methods. Submicroscopic c a r l s b a d a n d / o r a l b i t e c a r l s b a d as well as a l b i t e t w i n n i n g m i g h t be t h e cause of t h e o b s e r v e d differences. T h e c-reflections of t h e i n v e s t i g a t e d c r y s t a l s are w e a k a n d diffuse. O n l y one c r y s t a l from breccia 14301 h a s s h a r p a n d s t r o n g creflections. T h e c-reflections of all h e a t - t r e a t e d c r y s t a l s were less i n t e n s e a n d slightly m o r e diffuse a f t e r t h a n before h e a t i n g . Therefore, t h e a u t h o r s propose t h a t t h e s e plagioclases h a v e b e e n cooled f r o m a b o u t 1O00°C in a m u c h longer t i m e t h a n t h e cooling t i m e in t h e i r e x p e r i m e n t s (i.e., f r o m 1000°C d o w n to 300°C in l h r ) . DENCE, M. R., AND PLANT, A. G., 1972. A n a l y s i s of F r a M a u r o s a m p l e s a n d t h e origin of t h e I m b r i u m Basin. Geochim. Cosmochim. Acta Suppl. 3, 1, 379-399. Apollo 14 soils a n d rocks are p r e d o m i n a n t l y f r a g m e n t a l , a n d comprise glasses, g l a s s - b e a r i n g breccias, a n n e a l e d fragm e n t a l rocks, a n d a s m a l l p r o p o r t i o n of igneous rocks of b a s a l t i c t e x t u r e . T h e t e x t u r e s a n d c o m p o s i t i o n of glasses a n d rock f r a g m e n t s in soils 14258,34 a n d 14167,7 are r e p o r t e d a n d are s h o w n to be m a i n l y of four t y p e s : alkali-rich ( F r a Mauro) basalts, f e l d s p a t h i c ( H i g h l a n d ) b a s a l t s a n d a n o r t h o s i t e s , m a r e basalts, a n d p o t a s s i e granites. T h e s a m e c o m p o n e n t s are f o u n d in f r a g m e n t a l rocks. G l a s s - b e a r i n g breccia 14315,11 c o n t a i n s m a n y c h o n d r u l e - l i k e bodies a n d d e v i t r i f i e d glasses of f e l d s p a t h i c b a s a l t c o m p o s i t i o n . A n n e a l e d f r a g m e n t a l rocks 14305,5 a n d 14314,13 c o n t a i n a wide v a r i e t y of clasts including mineral fragments, mare basalt, and a n n e a l e d glass p r e d o m i n a n t l y of F r a M a u r o b a s a l t c o m p o s i t i o n enclosing smaller a m o u n t s of potassic g r a n i t e . F r a g m e n t a l rock 14311,88 is more thoroughly annealed and contains many v u g linings a n d inclusions of potassic g r a n i t e glass, some p a r t l y devitrified. Crystalline r o c k 14310,4 is a f e l d s p a t h i c b a s a l t w i t h a wide r a n g e of t e x t u r e a n d , b y a n a l o g y w i t h rocks f r o m t e r r e s t r i a l i m p a c t craters, is i n t e r p r e t e d as a n i m p a c t melt, in w h i c h coarser c r y s t a l s n u c l e a t e d a r o u n d relict x e n o c r y s t s . F r o m a n i m p a c t m o d e l for t h e I m b r i u m Basin, b a s e d o n studies o f t e r r e s t r i a l craters, t h e a r g u m e n t is d e v e l o p e d

t h a t t h e e j e c t a a t t h e F r a M a u r o site w e r e probably only weakly shocked and heated by t h e I m b r i a n e v e n t a n d were d e r i v e d f r o m t h o u p p e r m o s t c r u s t in t h e I m b r i u m B a s i n area. The multiple shock and thermal events recorded in t h e f r a g m e n t a l rocks a n d f e l d s p a t h i c b a s a l t s are considered to r e s u l t f r o m i n t e n s i v e m e t e o r i t e b o m b a r d m e n t p r i o r to t h e I m b r i a n i m p a c t . Some m a r e basalts also p r e d a t e t h i s e v e n t , b u t m o s t g l a s s - b e a r i n g breccias p r o b a b l y were o f later derivation. DOWTY, E., R o s s , M., AND CUTTITTA, F., 1972. F e 2 + - M g site d i s t r i b u t i o n in Apollo 12021 c l i n o p y r o x e n e s : E v i d e n c e for bias in M S s s b a u e r m e a s u r e m e n t s , a n d r e l a t i o n of o r d e r i n g t o exsolution. Geochim. Cosmochim. Acta Suppl. 3, 1, 481-492. M S s s b a u e r - d e r i v e d " c a t i o n distribution" numbers, and exsolution relationships f r o m single-crystal X r a y s t u d i e s are r e p o r t e d for t h r e e p y r o x e n e f r a c t i o n s f r o m rock 12021: M g - p i g e o n i t e , W o llEn~oFs29 ; M g - a u g i t e , WoaoEn43Fs27; a n d F e augite, Wo2~En2,Fsso. E a c h of t h e s e f r a c t i o n s h a s b e e n a n a l y z e d b y semimicro wet-chemical methods. For the Fe-augite, t h e M 6 s s b a u e r m e a s u r e m e n t s i n d i c a t e a n anom a l o u s " e x c e s s " of M2 cations. E r r o r in c h e m i c a l c h a r a c t e r i z a t i o n c a n b e e l i m i n a t e d as a cause o f t h i s a n o m a l y , because t h e s a m e s a m p l e was u s e d in b o t h M S s s b a u e r m e a s u r e m e n t s a n d c h e m i c a l analysis. C o n s i d e r a t i o n of e x s o l u t i o n r e l a t i o n s suggests a n e v e n g r e a t e r a n o m a l y for t h e F e augite. B e c a u s e it c o n t a i n s 5 0 % e x s o l v e d pigeonite, w h i c h t h e a u t h o r s e x p e c t to b e d i s o r d e r e d b y a n a l o g y w i t h t h e r e s u l t for t h e Mg pigeonite, t h i s f r a c t i o n s h o u l d b e p a r t i a l l y disordered in bulk, i.e., h a v e some m a g n e s i u m in M2. T h e a n o m a l y c a n be e x p l a i n e d as a r e s u l t of a bias in t h e M S s s b a u e r m e a s u r e m e n t s d u e to (1) differing local e n v i r o n m e n t s for iron a t o m s in M1, w h i c h " s p l i t s " t h e M1 a b s o r p t i o n , c a u s i n g some of it to lie u n d e r t h e M2 d o u b l e t a n d t h e r e b y e n h a n c i n g t h e l a t t e r ; a n d (2) n o n s u p e r p o s i t i o n of t h e M1 d o u b l e t s for t h e e x s o l v e d pigeonite a n d a u g i t e in e a c h f r a c t i o n ( X r a y studies show t h a t all t h e f r a c t i o n s are u n m i x e d ) . B o t h t h e s e t y p e s of bias h a v e b e e n d o c u m e n t e d in s y n t h e t i c clinopyroxenes. T h e bias is p r o b a b l y p r e s e n t in all M 6 s s b a u e r m e a s u r e m e n t s o f c l i n o p y r o x e n e s a n d m a y be large e n o u g h t o a c c o u n t for t h e d i s a g r e e m e n t b e t w e e n M 6 s s b a u e r and X ray results--previous M6ssbauer studies h a v e s u g g e s t e d t h a t o r d e r i n g increases w i t h t h e a m o u n t of calcium in clinopyroxenes, w h e r e a s X r a y r e f i n e m e n t s show j u s t t h e opposite. D~EVER, H . I., AND JOhNStON, R., 1972. M e t a s t a b l e g r o w t h p a t t e r n s in some t e r r e s t r i a l a n d l u n a r rocks. Meteoritics 7, 327 340. W i t h reference to n e w i n f o r m a t i o n o n t h e t e x t u r e s in

I~IrOO:N--SURFACE LAYER s o m e t e r r e s t r i a l mafic a n d u l t r a m a f i c igneous r o c k s o f T e r t i a r y age, t e x t u r a l p a t t e r n s a t t r i b u t a b l e to m e t a s t a b l e c r y s t a l l i z a t i o n are described, i l l u s t r a t e d a n d reviewed. T h e igneous t e x t u r a l t e r m i n o l o g y , e m p l o y e d in t h e descript i v e t e x t , is r e v i e w e d , a n d t h e use of c e r t a i n n e w t e r m s is a d v o c a t e d . C o m p a r e d w i t h t h e s e t e x t u r a l p a t t e r n s are t h e s k e l e t a l c r y s t a l g r o w t h a n d i n t e r g r o w t h in igneous r o c k s a m p l e s obt a i n e d , m a i n l y b y t h e Apollo 12 Mission, f r o m the moon. Both orientated and unorientated m c t a s t a b l e g r o w t h yield c h a r a c t e r i s t i c d e n d r i t i c or skeletal olivine crystals, a n d a t e x t u r e w h i c h h a s b e e n t e r m e d " i n t r a f a s c i c u l a t e " is also a t t r i b u t e d to m e t a s t a b l e c r y s t a l l i z a t i o n of plagioclase a n d p y r o x e n e . T h e t h r e e p r i n c i p a l t e r r e s t r i a l t e x t u r e s defined a n d d e s c r i b e d are "Willow Lake" texture, infrafasciculate texture and harrisitie texture. The term "thermotactic" is p r e f e r r e d t o " W i l l o w L a k e " or " c r e s c u m u l a t e " t o define a t e x t u r e w i t h o r i e n t a t i o n of c r y s t a l g r o w t h in t h e d i r e c t i o n of t h e t h e r m a l g r a d i e n t . A t t e n t i o n is d r a w n t o t h e i m p o r t a n c e in p e t r o genesis of s u c h m e t a s t a b l e c r y s t a l l i z a t i o n , as inferred from crystal growth and textural o b s e r v a t i o n s . I t is a p p a r e n t t h a t a n a l o g o u s "metastable" textures occur through a remarkable r a n g e in geological c o n t e x t . More d e t a i l e d w o r k is a d v o c a t e d on t h e p e g m a t i t i c e u c r i t e s a n d p e r i d o t i t e s of R h u m . Since t h e e v i d e n c e suggests t h a t t h e s e rocks r e p r e s e n t h y d r o u s u l t r a b a s i c liquids, n o t c u m u l a t e s , t h e c o n d i t i o n s g o v e r n i n g t h e g r o w t h of olivine in t h e m m u s t differ f r o m t h o s e of a n y l u n a r analog. DREVER, H . I., JOHNSTON, R., BUTLER, P., j m , AND GIBB, F. G. F., 1972. Some t e x t u r e s in Apollo 12 l u n a r igneous rocks a n d in t e r r e s t r i a l analogs. Geochim. Cosmochira. Acta Suppl. 3, 1, 171 184. T h e i n t e r p r e t a t i o n of i m m a t u r e crystall i z a t i o n a n d some l u n a r t e x t u r e s c h a r a c t e r i z e d b y it are t h e p r i n c i p a l o b j e c t i v e s of t h i s i n v e s t i g a t i o n . A c o m p a r a t i v e a n d selective a p p r o a c h is a d o p t e d , a n d p a r t i c u l a r reference is m a d e t o t h e f o r m a n d t e x t u r a l r e l a t i o n s of olivine in 12009 a n d of p y r o x e n e s a n d plagioclase i n 12021, a n d to t e r r e s t r i a l analogs. T h e optic o r i e n t a t i o n of t h e olivines in 12009 is d e t e r m i n e d a n d t h e i r skeletal c r y s t a l l i z a t i o n is i l l u s t r a t e d a n d e v a l u a t e d . M i c r o p r o b e a n d optical d a t a are a s s o c i a t e d in a t e x t u r a l a n a l y s i s of a n a n a l o g f r o m t h e u p p e r c o n t a c t of a m i n o r i n t r u s i o n in Skye. T h e optic o r i e n t a t i o n of p y r o x e n e enclosed i n plagioclase cores is d e t e r m i n e d a n d t h e results p l o t t e d s t e r e o g r a p h i c a l l y . T h e n e e d for g r e a t e r precision in t h e use of t e x t u r a l t e r m s is s t r e s s e d a n d a n e w t e r m , i n t r a f a s c i c u l a t e , i n t r o d u c e d for t e x t u r e s in w h i c h p y r o x e n e h a s c r y s t a l l i z e d w i t h i n hollow, s k e l e t a l plagioclase. Apollo 12

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p y r o x e n e p h y r i c b a s a l t s are t e x t u r a l l y r e v i e w e d a n d t h e c r y s t a l l i z a t i o n of t h e p h e n o c r y s t s discussed, e m p h a s i s b e i n g p l a c e d o n size-ind e p e n d e n c e of s k e l e t a l g r o w t h . O n t h e basis of evidence that immature crystallization of p y r o x e n e in a m e t a s t a b l e field is n o t confined t o q u e n c h e d liquids, it is i n f e r r e d t h a t in m a r e b a s a l t s , b o t h skeletal p h e n o c r y s t s a n d skeletal g r o u n d m a s s c r y s t a l s are t h e r e s u l t of supers a t u r a t i o n , t h e earlier s t a g e of lower n u c l e a t i o n d e n s i t y c o r r e s p o n d i n g t o a slightly lower d e g r e e of s u p e r s a t u r a t i o n . Similarities in t h e t e x t u r a l r e l a t i o n s h i p of p y r o x e n e a n d plagioclase, in t h e selected t e r r e s t r i a l a n a l o g s a n d in t w o Apollo 12 basalts, are c o r r e l a t e d b o t h o p t i c a l l y a n d chemically. I n t h e p y r o x e n e q u a d r i l a t e r a l , t h e c l i n o p y r o x e n e t r e n d lines i n d i c a t e as in lunar basalts, rapid metastable crystallization. Some of t h e m o r e p r o m i s i n g lines of a d v a n c e m e n t in solving p r o b l e m s of t e x t u r e a n d c r y s t a l g r o w t h in l u n a r b a s a l t s are s u m m a r i z e d . EL GORESY, A., TAYLOR, L. A., AND RAMDOHR, P., 1972. F r a M a u r o c r y s t a l l i n e rocks: Mineralogy, g e o c h e m i s t r y a n d subsolidus r e d u c t i o n o f t h e o p a q u e m i n e r a l s . Geochim. Cosmochim. Acta Suppl. 3, 1, 333-349. T h e o p a q u e m i n e r a l s o b s e r v e d in Apollo 14 c r y s t a l l i n e r o c k s a m p l e s (14053,2; 14072,12; 14073,7; 14310,101) are ilmenite, c h r o m i a n ulvSspinel, a l u m i n i a n t i t a n Jan c h r o m i t e , picotite, rutile, b a d d e l e y i t e , sehreibersite, n a t i v e F e N i m e t a l ; troilite, m a c k inawite, c h a l c o p y r r h o t i t e , a n d t r a n q u i l l i t y i t e . T e x t u r a l a n d m i n e r a l o g i c a l similarities e x i s t b e t w e e n rocks 14073 a n d 14310 v e r s u s 14053 a n d 14072. T h e Ni c o n t e n t of t h e n a t i v e F e N i m e t a l s in 14310 a n d 14073 r a n g e s b e t w e e n 1.5 a n d 3 7 w t % a n d 5.5 a n d 2 4 w t % Ni, respect i v e l y ; t h e r e is a preference of l~i for t h e m e t a l p h a s e a s s o c i a t e d w i t h troilite t h a t m a y b e a r e s u l t of t h e p r e v a i l i n g as2. T h e Co c o n t e n t is close to 0 . 5 % a n d t h e m e t a l grains h a v e m e t e o r i t e - t y p e compositions. I n 14053 a n d 14072, t h e Ni c o n t e n t of t h e m e t a l p h a s e r a n g e s f r o m <0.01 t o 4 . 8 w t % a n d b e t w e e n 0.2 a n d 6 . 1 w t % Ni, respectively, a n d is i n d e p e n d e n t of t h e m i n e r a l assemblage. Two coexisting schreib e r s i t e s were f o u n d in F e N i m e t a l g r a i n s o f 14310, one Ni-rich ( 2 8 w t % ) a n d t h e o t h e r ~ F e 3 P . R o c k s 14310 a n d 14073 m a y c o n t a i n m o r e b a d d e l e y i t e t h a n a n y l u n a r rock e x a m i n e d to d a t e . I t c o m m o n l y occurs w i t h i l m e n i t e ( c o n t a i n i n g u p t o 0 . 5 7 w t % ZrO2) a n d c h r o m i a n ulvSspinel (up t o 0 . 2 5 w t % ZrO2). Two t r a n q u i l l i t y i t e s were o b s e r v e d in 14310 ; one is similar t o the type material and the other contains ~ 4 w t % less ZrO2 a n d ~ 4 w t % m o r e (TiO2 ÷ SiO2). O n l y c h r o m i a n ulvSspinel was o b s e r v e d in 14073 a n d 14310, whereas, in a d d i t i o n ,

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AFCRL B I B L I O G R A P t I ¥ - - 3 R D QUARTER 1972

a l u m i n i a n - t i t a n i a n c h r o m i t e a n d p i c o t i t e occur in 14053 a n d 14072. T h e ulv6spinel in t h e l a t t e r t w o rocks is m u c h m o r e Cr rich t h a n in t h e former. S u b s o l i d u s r e d u c t i o n of e h r o m i a n u l v 6 s p i n e l to i l m e n i t e + a l u m i n i a n c h r o m i t e + n a t i v e F e occurs in 14053 a n d 14072, a n d t h e c o m p o s i t i o n a l t r e n d s of u l v 6 s p i n e l d u r i n g p r i m a r y c r y s t a l l i z a t i o n a n d subsolidus r e d u c t i o n are in a n opposite sense. MgO p a r t i t i o n i n g s b e t w e e n p r i m a r y i l m e n i t e a n d ulv6spinel versus " e x s o l v e d " i l m e n i t e a n d coexisting ulv6spinel i n d i c a t e t h a t t h e r e d u c t i o n process r e p r e s e n t s a closer a p p r o a c h to e q u i l i b r i u m t h a n initial c r y s t a l l i z a t i o n . I n a d d i t i o n , f a y a l i t e in 14053 shows b r e a k d o w n to n a t i v e F e + t r i d y m i t e + SiO2-rich glass. R o c k s 14053 a n d 14072 h a v e undergone more reducing conditions than any o t h e r Apollo l l , 12, or 14 l u n a r rock. FABEL, G. ~¥., WHITE, W. B., WHITE, E. ~¥., AND ROY, R., 1972. S t r u c t u r e of l u n a r glasses b y R a m a n a n d soft x - r a y spectroscopy. Geochim. Cosmochim. Acta Suppl. 3, 1, 939 951. X r a y spectra and Raman spectra have been measured f r o m i n d i v i d u a l particles of l u n a r glasses. E a c h p a r t i c l e was a n a l y z e d s e p a r a t e l y b y electron m i c r o p r o b e . Silicon emission shifts v a r y b e t w e e n p a r e n t rock t y p e s a n d c a n b e i n t e r p r e t e d as a r a n g e of Si O d i s t a n c e s f r o m 1.612 to 1.637A. A l u m i n u m emission shifts r e l a t e to t h e a m o u n t o f 4- a n d 6 - c o o r d i n a t e d A1 in t h e glass. R a m a n s p e c t r a show b r o a d e n e d b a n d s . C e r t a i n b a n d s r e c u r in m a n y specimens a n d relate to t h e m a i n n o r m a t i v e m i n e r a l s for t h e glass b u l k composit i o n , olivine, p y r o x e n e , a n d a n o r t h i t e . FLEISCHER, R. L., COMSTOCK, G. M., AND ]-IART, H. R., JR., 1972. Dating of mechanical events by deformation-induced erasure of particle tracks. J. Geophys. Res. 77, 5050-5053. Natural fine-scale plastic deformation of lunar pyroxenes has been observed to fragment preexisting charged-particle tracks. An observer using only an optical microscope would see only the tracks formed later and hence would measure the time when deformation occurred. In one sample the deformation was estimated to have occurred 20 25In.y. ago. FLORAN, R. J., CAI~IERON, K. L., BENCE, A. E., AND PAPIKE, J . J., 1972. Apollo 14 b r e c c i a 14313: A m i n e r a l o g i e a n d petrologic r e p o r t . Geochim. Cosmochim. Acta Suppl. 3, 1, 661 671. L u n a r s a m p l e 14313 is a c o h e r e n t p o l y m i e t breccia t h a t h a s h a d a c o m p l e x h i s t o r y of comminution and reagglomeration. The d o m i n a n t t y p e s of clasts are (1) n o r i t i c rock f r a g m e n t s , (2) m o n o m i n e r a l i c f r a g m e n t s , (3) m i c r o b r e c c i a clasts, a n d (4) glassy f r a g m e n t s i n c l u d i n g glass spherules. M a r e - t y p e b a s a l t e l a s t s arc rare. T h e m a t r i x of t h e breccia is

c o m p o s e d p r i m a r i l y of fine p a r t i c l e s of b r o w n i s h glass. P e t r o g r a p h i c e x a m i n a t i o n reveals v a r y i n g degrees of s h o c k d a m a g e of t h e clasts r a n g i n g f r o m u n s h o c k e d t h r o u g h s h o c k - m e l t e d fragments. Both thermally reerystallized and unr e e r y s t a l l i z e d m i c r o b r e e c i a clasts are p r e s e n t in 14313. T h e f o r m e r lack glass a n d h a v e a n annealed matrix, whereas the latter contain a b u n d a n t glass b o t h as elasts a n d in t h e i r m a t r i c e s . B a s e d on t h e c r i t e r i o n of brecciaw i t h i n - b r e c c i a , a sequence of four u n r e e r y s t a l lized m i e r o b r e e c i a s h a s b e e n recognized. T h e n u m b e r of i m p a c t e v e n t s n e e d e d to f o r m t h i s s e q u e n c e c a n n o t be d e t e r m i n e d u n i q u e l y , b u t t h e h i g h glass c o n t e n t a n d h i g h a v e r a g e level of s h o c k f e a t u r e s of t h e clasts in 14313 suggest m a n y e v e n t s . T h e a u t h o r s believe t h a t breccia 14313 was f o r m e d b y s h o c k lithifieation of regolith developed on the Fra Mauro formation. T h e a b u n d a n c e of m i c r o n o r i t e elasts suggests t h a t noritie rocks were a n i m p o r t a n t preI m b r i a n rock t y p e in t h e area n o w occupied b y t h e I m b r i u m Basin. B r e c c i a 14313 a p p e a r s to be a m u l t i - i m p a c t soil breccia w i t h g r e a t t e x t u r a l v a r i a t i o n a n d clast d i v e r s i t y reflecting a m a t u r e r e g o l i t h deposit. FORD, C. E., BIGGAR, G. M., HUMPHRIES, D. J., VV'ILSON, G., DIXON, D., AND O'HARA, M. J., 1972. Bole of w a t e r in t h e e v o l u t i o n of t h e l u n a r c r u s t ; a n e x p e r i m e n t a l s t u d y of s a m p l e 14310; a n i n d i c a t i o n of l u n a r eale-Mkaline v o l c a n i s m . Geochim. Cosmochim. A eta Suppl. 3, 1, 207-229. I n t e r s e r t a l f e l d s p a r - p h y r i c h i g h a l m n i n a b a s a l t , 14310, f r o m t h e F r a M a u r o f o r m a t i o n h a s a n o r t h i t e as l i q u i d u s p h a s e a t a p p r o x i m a t e l y 1310°C a t pressures to as m u c h as 1 2 k b ( ~ 2 5 0 k m d e p t h ) w h e r e it is r e p l a c e d first b y spinel, a n d t h e n b y g a r n e t a t pressures greater than approximately 17kb (~350km d e p t h ) . Olivine is t h e n e x t silicate to crystallize a t low pressures (~1230°C), b u t is r e p l a c e d in t h i s role b y one or m o r e p y r o x e n e s a t p r e s s u r e s g r e a t e r t h a n 4 k b . Olivine reacts o u t o n cooling a t a t m o s p h e r i c pressure, c a l c i u m - p o o r p y r o x e n e being the product at temperatures between 1200°C a n d l l 6 0 ° C . T h e p r e s e n t b u l k comp o s i t i o n of 14310 c o n t a i n s too little o x y g e n to keep all t h e iron oxidized as FeO, or to m a i n t a i n a Fee+/Mg 2+ r a t i o in t h e liquid h i g h e n o u g h to p r e c i p i t a t e t h e r e l a t i v e l y iron e n r i c h e d pigeonites formed during the natural crystallization, and l a t e stage loss of o x y g e n b y v o l a t i l i z a t i o n is evident. The highly aluminous phases present on t h e l i q u i d u s are u n s u i t a b l e as m a j o r r e s i d u a l c o n s t i t u e n t s of t h e l u n a r i n a n t l e a n d 14310 c a n n o t be a p r i m a r y m a g m a f r o m t h a t source. W a t e r a n d alkalis m a y also h a v e b e e n lost b y p o s t e r u p t i o n v o l a t i l i z a t i o n : a d d i t i o n of t h e s e

M O O N - - S U R F A C E LAYER

c o m p o n e n t s t o 14310 p r o d u c e s a m a g m a n e a r l y e o t e c t i c w i t h t h e m i n e r a l s of s p i n e l - t r o c t o l i t e a t low p r e s s u r e s ( ~ 2 5 0 b a r s ) a n d s u c h rocks are o b s e r v e d in t h e hreccias. T h e a u t h o r s d e d u c e t h a t 14310 is a v o l a t i l e d e p l e t e d s a m p l e of l i q u i d f r o m a shallow s e a t e d f r a c t i o n a t i n g m a g m a c h a m b e r c o n t a i n i n g a l i q u i d of calca l k a l i n e affinities. GARLICK, G. F. J., STEIGMA~N~, G. A., AND LAMB, W. E., 1972. Effect of fluidization o n t h e p o l a r i z a t i o n of reflected l i g h t f r o m l u n a r d u s t layers. Nature 238, 13-14. W h e n fluidization occurs t h e p o s i t i v e b r a n c h of t h e curves, t h a t is, t h a t a t p h a s e angles g r e a t e r t h a n 20 °, shows a m a r k e d increase o v e r t h e s t a t i c c u r v e a n d in some cases t h e p e a k p o l a r i z a t i o n rises b y m o r e t h a n 1 0 0 % . V e r y little c h a n g e is o b s e r v e d in t h e n e g a t i v e p o l a r i z a t i o n region of t h e c u r v e s a t s m a l l p h a s e angles b u t w h e n it does occur t h e effect is to r e d u c e t h e n e g a t i v e p o l a r i z a t i o n . GAST, P. W., 1972. T h e c h e m i c a l c o m p o s i t i o n a n d s t r u c t u r e of t h e Moon. The M o o n 5, 121 148. See M o o n - - F i g u r e a n d I n t e r n a l S t r u c t u r e . GAY, P., Bow-'% M. G., AND MUIR, I. D., 1972. Mineralogical a n d p e t r o g r a p h i c f e a t u r e s of t w o Apollo 14 rocks. Geochim. Cosmochim. Acta S u p p l . 3, 1, 351 362. P e t r o g r a p h i c d e s c r i p t i o n s are g i v e n of 14310, a f e l d s p a r p h y r i c higha l n m i n a b a s a l t rich in pigeonite, a n d of 14321, a c o m p l e x m i c r o b r e c e i a c o n t a i n i n g m a n y diff e r e n t t y p e s of clasts a n d igneous rock f r a g m e n t s . Textures and very unnsual compositional zoning in t h e plagioclase of t h e b a s a l t i n d i c a t e t h a t it c o m p l e t e d c r y s t a l l i z a t i o n a t or n e a r t h e surface w i t h a loss of soda to a p r e s u m e d v a p o r phase. A d e t a i l e d s t u d y of 14321 reveals some u n e x p e c t e d p o s t c r y s t a l l i z a t i o n reactions, i n c l u d i n g t h e e x s o l u t i o n of oxide p h a s e s f r o m p y r o x c n e s a n d olivines. C o m p a r i s o n w i t h a n a l o g o u s terrest r i a l o c c u r r e n c e s suggests t h a t some f r a g m e n t s of 14321 were t h e r m a l l y m e t a m o r p h o s e d before i n c o r p o r a t i o n i n t o t h e microbreccia. Oxide p h a s e s could h a v e b e e n p r o d u c e d , e v e n u n d e r n e a r v a c u u m c o n d i t i o n s , in m e t a s t a b l e initial c r y s t a l s c o m p o s i t i o n a l l y different f r o m t h e i r terrestrial counterparts ; alternatively, the metam o r p h i s m could h a v e o c c u r r e d u n d e r w e a k l y oxidizing c o n d i t i o n s , w h i c h could b e i m p o r t a n t i n t h e d e t a i l e d c r y s t a l l i z a t i o n h i s t o r y of t h e l u n a r surface. GtlOSE, S., 2~G, G., AND WALTEI~, L. S., 1972. C l i n o p y r o x e n e s f r o m Apollo 12 a n d 14: E x solution, d o m a i n s t r u c t u r e , a n d c a t i o n order. Geochim. Cosmochim. Acta S u p p l . 3, 1, 507-531. Core p i g e o n i t e s f r o m r o c k 12053 show v e r y s m a l l a m o u n t s of fine-scale e x s o l u t i o n l a m e l l a e of augite, p r e s u m a b l y parallel t o (001). T h e b-type (h + k odd) X r a y reflections are v e r y

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diffuse a n d are s t r e t c h e d parallel to a*. R i m subcalcic a u g i t e f r o m t h e s a m e r o c k shows t h e s m a l l e s t s e p a r a t i o n in /~-angles ( A f t = l°35 ') between the host augite and exsolved pigeonite phases. Subcalcic a u g i t e f r o m r o c k 12038 s h o w s l a r g e r / I / ~ (2°i7 ') a n d s h a r p e r e x s o l v e d p i g e o n i t e spots. I n b o t h rocks t h e e x s o l v e d p i g e o n i t e s p o t s are c o n n e c t e d t o t h e c o r r e s p o n d i n g a u g i t e s p o t s b y s t r o n g diffuse s t r e a k s . A s e c o n d g e n e r a t i o n of v e r y fine-scale (00I) e x s o l u t i o n lamellae in subcalcic augites f r o m b o t h rocks are r o t a t e d a b o u t 1 ° (b as t h e r o t a t i o n axis) f r o m t h e o r i e n t a t i o n of t h e first g e n e r a t i o n (001) lamellae. C a t i o n o r d e r d e t e r m i n e d b y M 6 s s b a u e r resona n c e s p e c t r o s c o p y in pigconites f r o m b o t h r o c k s is high, t h e K D v a l u e s for p i g e o n i t e s f r o m r o c k s 12053 a n d 12038 b e i n g 0.086 a n d 0.030, respectively. P i g e o n i t e s f r o m r o c k 12040 c o n t a i n o n l y one set of v e r y fine-scale a u g i t e e x s o l u t i o n lamellae parallel to (001), r o t a t e d b y HI ° w i t h r e s p e c t t o t h e h o s t pigeonite. T h e s e secondg e n e r a t i o n lamellae i n d i c a t e t h a t t h e s e rocks m u s t h a v e b e e n s u b j e c t e d to r e h e a t i n g for c o n s i d e r a b l e p e r i o d of t i m e , following initial cooling a f t e r c r y s t a l l i z a t i o n f r o m t h e m e l t . I n c o n t r a s t , pigeonites f r o m rock 12021 show t w o sets of e x s o l v e d a u g i t e laInellae parallel to (001) a n d (100), w i t h s h a r p a u g i t e spots, s h a r p b - t y p e reflections a n d a fairly h i g h degree of c a t i o n o r d e r ( K D - 0.097). This i n d i c a t e s a c o n t i n u o u s cooling of t h i s r o c k a t a slow rate, w i t h n o e v i d e n c e for a s u b s e q u e n t r e h e a t i n g . T h e e x s o l u t i o n b e h a v i o r in pigconites f r o m r o c k s 14310 a n d I4053 are similar, b o t h s h o w i n g l a r g e s e p a r a t i o n in fi angles f r o m e x s o l v e d a u g i t e a n d p i g c o n i t e (Aft = 2°30 ' t o 2°50'). T h e c o r r e s p o n d ing a u g i t e a n d p i g e o n i t e spots are c o n n e c t e d b y f a i n t diffuse s t r e a k s . T h e b-type reflections a r e fairly s h a r p . H o w e v e r , t h e degree of c a t i o n d i s o r d e r in p i g e o n i t e f r o m rock 14053 (K D = 0.127) is m u c h h i g h e r t h a n t h a t in p i g e o n i t e f r o m rock 14310 (K D = 0.094). B o t h rocks h a v e cooled fairly slowly a f t e r c r y s t a l l i z a t i o n f r o m t h e m e l t . R o c k 14053 h a s s u b s e q u e n t l y b e e n r e h e a t e d to a t e m p e r a t u r e h i g h e r t h a n 840°C for a s h o r t d u r a t i o n . T h e size of t h e d o m a i n s in p i g e o n i t e (as o b s e r v e d t h r o u g h t h e e l e c t r o n microscope by imaging through the b-type reflections) increases p r o g r e s s i v e l y in t h e o r d e r : 12053 (50 to 100A), 12038 ( ~ 5 0 0 A ) , 12021 (~1000/~), 14310 (~1500~-). V i e w e d d o w n t h e b-axis t h e s h a p e of t h e d o m a i n s are b l o c k y a n d are slightly e l o n g a t e d parallel t o t h e c-axis. GLASS, B. P., STORZER, D., ASrD ~rAGlgER, G. A., 1972. C h e m i s t r y a n d p a r t i c l e t r a c k s t u d i e s of Apollo 14 glasses. Geochim. Cosmochim. Acta Suppl. 3, 1, 927 937. Apollo 14 glasses f r o m t h e < l m m fines c a n be d i v i d e d i n t o five m a j o r

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AFCRL BIBLIOGI:tAPI:IY--31~D QUARTER 1 9 7 2

g r o u p s b a s e d o n t h e i r m a j o r e l e m e n t composition. O f t h e 282 glass p a r t i c l e s a n a l y z e d , m o s t (group 4) h a v e c o m p o s i t i o n s similar to t h e Apollo 14 soils a n d breccias. These glasses are s i m i l a r in c o m p o s i t i o n to t h e K R E E P glasses f o u n d in Apollo 12 fines. F e l d s p a t h i c glasses (group 2) w i t h h i g h A12Oa ( > 2 1 % ) a n d CaO ( > 1 5 % ) c o n t e n t s m a k e u p a b o u t 2 0 % of t h e glass p a r t i c l e s a n a l y z e d . T h i s is t h e o n l y glass t y p e t h a t h a s b e e n f o u n d a t all of t h e l u n a r l a n d i n g sites, a n d it was p r o b a b l y d e r i v e d f r o m t h e h i g h l a n d s . Glasses w i t h h i g h F e O ( > 1 4 % ) a n d low AlaO a ( < 1 5 % ) c o n t e n t s m a k e u p 17 to 3 0 % of t h e a n a l y z e d glasses. These glasses are p r o b a b l y d e r i v e d f r o m m a r i a regions. Glasses w i t h low NaaO a n d K 2 0 ( < 0 . 4 % ) c o n t e n t s (group 5) m a y h a v e b e e n affected b y v a p o r f r a c t i o n a t i o n . A small n u m b e r ( < 5 % ) of t h e glasses h a v e a n o r t h i t e compositions. T r a c k a n a l y s e s of t w e l v e of t h e glass particles were c a r r i e d o u t in o r d e r to d e t e r m i n e t h e i r u r a n i u m c o n t e n t s a n d r a d i a t i o n histories. T h e u r a n i u m c o n t e n t s were f o u n d to r a n g e b e t w e e n 0.2 a n d 17 p p m w i t h u r a n i u m c o r r e l a t i n g w i t h K 2 0 c o n t e n t . A s s u m i n g a m e a n b u r i a l d e p t h of 5 era, r a d i a t i o n ages b e t w e e n 105 a n d 107 years were found. GOPAL, R., AND CALVO, C., 1972. S t r u c t u r a l r e l a t i o n s h i p of w h i t l o e k i t e a n d /~Ca3(PO4) 2. N a t u r e 237, 30 32. See Meteors a n d Meteorites. GOSE, ~r. A., PEARCE, G. W., STRANG~,VAY, D. W., AND LARSON, E. E., 1972. O n t h e applicab i l i t y of l u n a r breccias for p a l e o m a g n e t i e interp r e t a t i o n s . The M o o n 5, 106-120. See M o o n - Figure and Internal Structure.

GRAY, N., HAFNER, S. S,, SCHURMANN, K., AND VIRGO, D., 1972. D i s t i n c t cooling histories o f Apollo 15 basalts. N a t u r e 236, 71-73. T h e n a t u r a l Mg 2+, F e 2+ d i s t r i b u t i o n in t h e 14310 o r t h o p y r o x e n e is i n d i c a t i v e of a cooling r a t e w h i c h c o r r e s p o n d s to t h e d e p t h of several m e t r e s f r o m t h e surface of a l a v a flow-. This is c o n s i s t e n t w i t h m i n e r a l o g i c a l a n d petrological s t u d i e s of t h i s rock w h i c h suggests c r y s t a l l i z a t i o n in n e a r - s u r f a c e c o n d i t i o n s . I t is also c o n s i s t e n t w i t h t h e s u g g e s t i o n t h a t 14310 m a y h a v e b e e n c r y s t a l l i z e d f r o m a m o l t e n p o c k e t in t h e e j e c t a b l a n k e t a t F r a Mauro. T h e Mg z+, F e 2+ d i s t r i b u t i o n in t h e pigeonite s e p a r a t e d f r o m b a s a l t 14053 is c o n s i d e r a b l y disordered. This is i n d i c a t i v e of e x t r e m e l y r a p i d cooling w h i c h c a n n o t occur deep in a l a v a flow. I t a p p e a r s t h a t t h e n o r m a l cooling process of b a s a l t 14053 was i n t e r r u p t e d a t a t e m p e r a t u r e >840°C a n d t h a t t h e rock was t h e n q u e n c h e d e x t r e m e l y r a p i d l y . Calculations s u g g e s t t h a t t h e p o r t i o n of 14053 s t u d i e d cooled f r o m a t e m p e r a t u r e a b o v e 800°C t o below 480°C a t a r a t e of several degrees r a i n - l . T h e r a p i d

cooling during the Fra impact

may have resulted from either radiation t h e flight t i m e f r o m Mare I m b r i u m to M a u r o region or b y c o n d u c t i o n a f t e r t h e in a cold regolith. GREEN, D. H., WARE, •. a . , AND HIBBERSON, W. O., 1972. E x p e r i m e n t a l e v i d e n c e a g a i n s t t h e role of selective v o l a t i l i z a t i o n o n t h e l u n a r surface. N a t u r e 238, 450-452. I t h a s b e e n s u g g e s t e d t h a t t h e d e d u c e d s e q u e n c e of crystall i z a t i o n a n d o b s e r v e d c h e m i c a l z o n i n g in plagioclase of a f e l d s p a r - r i c h l u n a r b a s a l t ( F r a M a u r o 14310) p r o v i d e s e v i d e n c e for selective v o l a t i l i z a t i o n of s o d i u m a n d p o t a s s i u m f r o m l u n a r m a g m a s d u r i n g e r u p t i o n a n d flow a t t h e l u n a r surface. Tile a u t h o r s c o n c l u d e t h a t t h i s rock r e p r e s e n t s r a p i d cooling a n d c r y s t a l l i z a t i o n of a liquid of t h e s a m e c o m p o s i t i o n as t h e p r e s e n t rock. T h e p r e s e n c e of sodic r i m s to plagioclase c r y s t a l s is d u e to l a t e - s t a g e e n r i c h m e n t in N a a n d K in local, i n t e r s t i t i a l , residual liquids. E x p e r i m e n t s show" t h a t tile p r e c i p i t a t i o n of plagioelase of t h e c o m p o s i t i o n s o b s e r v e d in the natural phenocrysts and groundmass requires t h a t t h e p a r e n t a l liquid h a v e t h e s a m e C a / N a a n d C a / K ratios as t h e p r e s e n t rock. T h e h y p o thesis t h a t t h e p r e s e n t rock lost > 6 0 % NazO a n d KeO d u r i n g e r u p t i o n a t t h e l u n a r surface is s h o w n to be i n c o m p a t i b l e w i t h t h e p r e s e n c e of a n o r t h i t e p h e n o c r y s t s . T h e m a t c h i n g of t h e n a t u r a l c r y s t a l l i z a t i o n s e q u e n c e in 14310, like t h a t of m a r e b a s a l t s p r e v i o u s l y s t u d i e d , w i t h those observed experimentally, demonstrates t h a t t h e r e h a s b e e n n o q u a n t i t a t i v e loss of alkalis b y v a c u u m v o l a t i l i z a t i o n d u r i n g e r u p t i o n of m a g m a s a t t h e h m a r surface. GREEN, D. H., RINGWOOD, A. E., WARE, N. G., AND HIBBERSON, W. O., 1972. E x p e r i m e n t a l p e t r o l o g y a n d petrogenesis of Apollo 14 basalts. Geochim. Cosmochim. A c t a S u p p l . 3, 1, 197 206. S a m p l e 14310 a n d a m o d e l K R E E P c o m p o s i t i o n h a v e been s t u d i e d e x p e r i m e n t a l l y as e x a m p l e s of t h e n o n m a r e b a s a l t i c c o m p o s i t i o n s t h a t are r e p r e s e n t e d a t t h e F r a M a u r o l a n d i n g site. R e s u l t s of e x p e r i m e n t a l m e l t i n g studies a t 1 atmosphere, compared with the observed m i n e r a l o g y in 14310, show t h a t t h e m i n e r a l o g y of 14310 f o r m e d d u r i n g c r y s t a l l i z a t i o n a t or n e a r t h e l u n a r surface. D e t a i l e d s t u d y of t h e roles of plagioclase, olivine, pigeonite, a n d o r t h o p y r o x ene c r y s t a l l i z a t i o n i n e x p e r i m e n t s a n d in t h e n a t u r a l r o c k leads t o t h e inference t h a t 14310 cooled r e l a t i v e l y slowly to ~1180°C a n d t h e n was m o r e r a p i d l y q u e n c h e d , e l i m i n a t i n g e v i d e n c e for e a r l y t r a n s i e n t olivine p r e c i p i t a t i o n b u t p r e s e r v i n g m a g n e s i a n p i g e o n i t e (in p a r t inv e r t e d to o r t h o p y r o x e n e ) cores in z o n e d p y r o x enes crystallized a t T < 1180°C. I t is i n f e r r e d t h a t 14310 was a n i m p a c t m e l t of p r e - I m b r i a n

MOON--SURFACE LAYEI~ regolith. H i g h - p r e s s u r e s t u d i e s of 14310 a n d K R E E P c o m p o s i t i o n suggest p r i m a r y d e r i v a t i o n of n o n m a r e b a s a l t i c c o m p o s i t i o n s f r o m a p l a g i o c l a s e - b e a r i n g source region in t h e o u t e r 2 0 0 k m of t h e m o o n . I t is c o n c l u d e d t h a t t h e m o o n is c h e m i c a l l y zoned, t h e o u t e r 2 0 0 k m h a v i n g significantly h i g h e r MgO/(MgO + FeO) and U/K ratios together with a higher abundance of A1 a n d p e r h a p s Ca, r e l a t i v e to t h e region below 2 0 0 k m w h i c h was t h e source of m a r e b a s a l t s . T h i s c h e m i c a l z o n a t i o n a p p e a r s to b e a primary feature established during the a c c r e t i o n process. GREENWOOD, W . R., MORRISON, D. A., AND CLARK, A. L., 1972. P h e n o c r y s t fabric in l u n a r b a s a l t s a m p l e 12052 f r o m t h e O c e a n of S t o r m s . Geol. Soc. A m e r . Bull. 83, 2809-2816. P y r o x e n e p h e n o c r y s t s in Apollo 12 s a m p l e 12052, a p o r p h y r i t i c b a s a l t , h a v e a weak, p l a n a r p r e f e r r e d o r i e n t a t i o n a n d a l i n e a t i o n as d e t e r m i n e d b y crystal-elongation measurements and universals t a g e m e a s u r e m e n t s in o r t h o g o n a l t h i n sections. T h e s t r u c t u r e s are p r o b a b l y t h e r e s u l t of l a m i n a r flow. N u m e r o u s v u g s a n d t h e flow foliation in s a m p l e 12052 suggest c r y s t a l l i z a t i o n as a surface flow or a n e a r - s u r f a c e sill. F l o w a g e a p p e a r s to h a v e ceased b y t h e t i m e of crystallizat i o n of t h e variolitic g r o u n d m a s s of t h e s a m p l e . T h e fabric d a t a suggest a t w o - s t a g e crystallizat i o n of s a m p l e 12052. (IRJEBINE, T., LAMBERT, G., AND LEROULLEY, J . C., 1972. A l p h a s p e c t r o m e t r y of a surface e x p o s e d h m a r rock. E a r t h Planet. Sci. Lett. 14, 322-324. Surface a l p h a r a d i o a c t i v i t y of a m o o n r o c k was m e a s u r e d in o r d e r to find t h e a c t i v i t y of 2mPo w h i c h c o u l d be d e s i g n a t e d as a desc e n d a n t of r a d o n o u t g a s s e d f r o m t h e l u n a r soil. N o surface a c t i v i t y was f o u n d w i t h i n s t a t i s t i c a l e r r o r limits. I f s u c h a process does exist a n d t h e d e p o s i t r e m a i n s o n t h e rock, it m u s t be s m a l l e r t h a n 2 × 1 0 - S d p s / c m a. I t is p r o p o s e d t h a t t h e a b s e n c e of t h i s p h e n o m e n o n m a y b e a t t r i b u t e d t o v a c u u m a n d t h e r m a l c o n d i t i o n s in t h e l u n a r soil. HAGGERTY, S, E., 1972. Apollo 14: S u b s o l i d u s r e d u c t i o n a n d c o m p o s i t i o n v a r i a t i o n s of spinels. Geochim. Cosmoehim. Aeta S u p p l . 3, 1, 305-332. :Reflection m i c r o s c o p y a n d e l e c t r o n m i c r o p r o b e a n a l y s e s u n d e r t a k e n on spinels of diverse origin a n d c o m p o s i t i o n , in s a m p l e s f r o m t h e Apollo 14 site, show t h a t t h e s e spinels are s t r u c t u r a l l y of t w o classes a n d c o n s t i t u t e t w o s e p a r a t e solid s o l u t i o n series: one is b e t w e e n (FeA1204FeCr204) a n d Fe2TiO,, t h e n o r m a l - i n v e r s e series ; a n d a s e c o n d is b e t w e e n MgA1204 a n d FeA12Oa, t h e n o r m a l series. M e m b e r s of t h e n o r m a l spinel series are defined c o m p o s i t i o n a l l y as p l e o n a s t e ; t h e n o r m a l - i n v e r s e series is a c o n t i n u o u s

93

c r y s t a l l i z a t i o n series f r o m e a r l y M g - a l u m i n i a n c h r o m i t e , to i n t e r m e d i a t e A l - t i t a n i a n - c h r o m i t e , and late stage Cr-Al-ulvSspinel. Compositional d i s c o n t i n u i t i e s are identified w i t h i n a n d b e t w e e n t h e s e series. E a r l y f o r m e d c h r o m i t e s are charact e r i z e d b y h i g h A120 a ( 1 8 - 2 0 % ) c o n t e n t s c o m p a r a b l e o n l y t o t h o s e in t h e L u n a 16 samples, a n d b y i n t e r m e d i a t e c o m p o s i t i o n s in t h e n o r m a l i n v e r s e series c o m p a r a b l e o n l y to spinels f r o m Apollo 11. P l e o n a s t e s are z o n e d c o m p o s i t i o n a l l y w i t h Mg-A1 cores a n d F e Cr-rich m a n t l e s . T h e p r o b a b i l i t y t h a t B site c o o r d i n a t e d F e 2+ a n d Ti 4+ are m o b i l i z e d selectively d u r i n g subsolidus r e d u c t i o n is d e m o n s t r a t e d , a n d b e c a u s e of t h e h i g h o c t a h e d r a l site preference energies of Cr a+ a n d A13+, t h e s e p r o p e r t i e s h a v e led to a definitive q u a n t i t a t i v e i n d e x r e f e r r e d to as t h e TAC r e d u c t i o n i n d e x TiOe/(TiO2 + AI:O a + Cr203), w h i c h p e r m i t s i n t e r c o r r e l a t i o n a n d c o m p a r i s o n of i n t e n s i t i e s of r e d u c t i o n w i t h i n a n d b e t w e e n samples. T h e TAC i n d e x reveals t h a t low i n t e n s i t y r e d u c t i o n is h e t e r o g e n e o u s (TAC = 0.6-0.9), w h e r e a s h i g h i n t e n s i t y (TAC = 0.35-0.50) results in a m o r e u n i f o r m l y r e d u c e d sample, a n d t h i s is i n t e r p r e t e d to i n d i c a t e t h a t low i n t e n s i t y is a s s o c i a t e d w i t h d e u t e r i c cooling a n d t h a t h i g h i n t e n s i t y results a t h i g h t e m p e r a tures. F u r t h e r m o r e t h e w i d e s p r e a d o c c u r r e n c e of t h e low i n t e n s i t y a s s e m b l a g e a t all five l u n a r l a n d i n g sites suggests a c o m m o n l y o c c u r r i n g process a n d is in c o n t r a s t to t h e h i g h i n t e n s i t y a s s e m b l a g e w h i c h b e c a u s e of its r a r i t y is m o r e likely l i n k e d to s p o r a d i c selenological e v e n t s . HAGGERT¥, S. E., 1972. Solid solution, subsolidus r e d u c t i o n a n d c o m p o s i t i o n a l c h a r a c teristics of spinels in some Apollo 15 b a s a l t s . Meteorities 7, 353-370. C o m p o s i t i o n a l d a t a for spinels i n t h e c h r o m i t e - h e r c y n i t e - u l v 6 s p i n e l s y s t e m f r o m t h r e e large b a s a l t s a n d for spinels in 48 b a s a l t p a r t i c l e s in four soil s a m p l e s s h o w : ( 1 ) t h a t t h e r a n g e of c o m p o s i t i o n s are c o m p a r a b l e to t h o s e of spinels in Apollo 12 b a s a l t s ; (2) t h a t t h e spinel series is c o m p l e t e b e t w e e n 0.75 FeCr204, 0.25 FeA1204, a n d Fe2TiO4; (3) t h a t t h e Apollo 12 b i m o d a l d i s t r i b u t i o n is p r e s e n t insofar as c h r o m i t e - r i c h a n d u l v 6 s p i n e l - r i c h p h a s e s are m o r e c o m m o n l y p r e s e n t t h a n compositions intermediate between these two end m e m b e r s ; (4) well-defined ionic r e l a t i o n s h i p s exist for t h o s e c a t i o n s d i s p l a y i n g h i g h o c t a h e d r a l site p r e f e r e n c e energies in t h e spinel s t r u c t u r e (viz. Cr v s A1 a n d Ti v s Cr + A1); (5) c a t i o n s d i s p l a y i n g low site p r e f e r e n c e energies (Fe 2+, Mg) show p o o r c o r r e l a t i o n ; a n d (6) t h e a b s e n c e of a simple r e l a t i o n s h i p b e t w e e n t h e d i v a l e n t ions (Fe 2+ a n d Mg), a n d t h e p a u c i t y ( < 1 0 % of 356 analyses) of i n t e r m e d i a t e c o m p o s i t i o n s suggests a s t r o n g d e p e n d e n c e o n t h e s t r u c t u r a l

94

AFeRL BIBLIOGRAPHY--3RD QUARTER 1972

s t a b i l i t y of i n t e r m e d i a t e m e m b e r s o f a n o r m a l ( h e r c y n i t e , c h r o m i t e ) - i n v e r s e ( u l v 6 s p i n e l ) solid s o l u t i o n series. HAPKE, B., 1972. Reflection s p e c t r a of l u n a r d u s t g r a i n s w i t h a m o r p h o u s coatings. Science 177, 535-536. B i b r i n g et al. suggest t h a t t h e low a l b e d o s a n d r e d d i s h s p e c t r a o f t h e l u n a r fines m a y b e d u e in p a r t t o coatings. T h e i r s u p p o r t i n g calculation, h o w e v e r , is i r r e l e v a n t t o t h e p r o b l e m of t h e l u n a r a l b e d o b e c a u s e it ignores t h e r e f r a c t e d ray. I t is s h o w n t h a t t h e c o a t i n g s h a v e o n l y a m a r g i n a l effect o n l u n a r reflectivity. ~IELSLEY, C. E., 1972. T h e significance of t h e m a g n e t i s m o b s e r v e d in l u n a r rocks. The Moon 5, 158-160. See M o o n - - F i g u r e a n d I n t e r n a l Structure. HELZ, R . T., 1972. R o c k 14068: A n u n u s u a l l u n a r breccia. Geochira. Cosmochira. Acta Suppl. 3, 1, 865-886. R o c k 14068 consists chiefly of a n olivine-rich g r o u n d m a s s (25% olivine in t h e n o r m ) w i t h t h e t e x t u r e of a r a p i d l y cooled i g n e o u s rock. This t e x t u r e is t e n t a t i v e l y a s c r i b e d to t h e q u e n c h i n g of a m e l t p r o d u c e d b y m e t e o r i t e i m p a c t . T h e g r o u n d m a s s includes a v a r i e t y of m i n e r a l a n d lithie clasts. I t is b o r d e r e d o n t h r e e sides b y a fringe of b l a c k microbreccia, w h i c h c o n t a i n s a suite of m i n e r a l a n d lithic clasts q u i t e different f r o m t h o s e i n c l u d e d in t h e m e l t e d g r o u n d m a s s . T h e p r e s e n c e of t h e s e two comp o n e n t s suggests t h a t rock 14068 is too h e t e r o geneous to b e i n c l u d e d in W a r n e r ' s (1972) classification. T h e a p p a r e n t c r y s t a l l i z a t i o n seq u e n c e of t h e olivine-rich g r o u n d m a s s , w i t h a v e r a g e o b s e r v e d compositions, is: olivine (Fo79), plagioclase (Ab2oAn72Ors) , a n d lowc a l c i u m p y r o x e n e (W%EnTsFsl9). A b s e n c e of high-calcium pyroxene indicates noritic rather t h a n b a s a l t i c affinities; h o w e v e r , olivine- a n d soda-rich members of a lunar noritic suite have n o t y e t b e e n described. HOUSLEY, R. M., GRANT, R. W., AND ABDELGAWAD, M., 1972. S t u d y of excess F e m e t a l in t h e l u n a r fines b y m a g n e t i c s e p a r a t i o n , M6ssb a u e r spectroscopy, a n d microscopic e x a m i n a t i o n . Geochim. Cosmochim. Acta Suppl. 3, 1, 1065-1076. A simple a n d c o n v e n i e n t m e t h o d of making quantitative magnetic separations has b e e n a p p l i e d to t h e l u n a r fines. T h e f r a c t i o n s obtained form groups containing distinctively different p a r t i c l e t y p e s ; t h u s , i t a p p e a r s t h a t m a g n e t i c s e p a r a t i o n in itself m a y be a useful w a y of c h a r a c t e r i z i n g l u n a r fines. M 6 s s b a u e r s t u d i e s of fines 10084 show t h a t t h e m e t a l c a n n o t c o n t a i n m o r e t h a n a b o u t 1.5% Ni, i m p l y i n g t h a t b y f a r t h e b u l k of t h e m e t a l results from reduction rather than from direct m e t e o r i t i c a d d i t i o n . M 6 s s h a u e r d a t a also place a n u p p e r l i m i t on t h e m a g n e t i c c o n t e n t of t h e

fines a p p r o x i m a t e l y a n o r d e r of m a g n i t u d e below t h a t r e q u i r e d to a c c o u n t for t h e c h a r a c t e r i s t i c f e r r o m a g n e t i c r e s o n a n c e o b s e r v e d . Microscopic e x a m i n a t i o n of m a g n e t i c s e p a r a t e s f r o m 15101 fines suggests t h a t r e d u c t i o n of F e accomp a n i e s e v e r y m a j o r i m p a c t e v e n t o n t h e moGn, a n d also t h a t t h e b u l k of t h e m a t e r i a l a t t h e collection site h a s a t one or m o r e t i m e s b e e n in an impact plume. JAGODZINSKI, H., AND KOREKAWA, M., 1972. X - r a y i n v e s t i g a t i o n s of l u n a r plagioclases a n d p y r o x e n e s . Geochim. Cosmochim. Acta Suppl. 3, 1, 555 568. T h e t h e o r y of X r a y diffraction o f lamellar systems with an incongruent and a c o n g r u e n t p l a n e of i n t e r g r o w t h is d e v e l o p e d . F o r small t h i c k n e s s e s of l a m e l l a e c o n s i d e r a b l e d e v i a t i o n s from t h e usual " i n c o h e r e n t " calculat i o n occur. Effects of t h i s k i n d are o b s e r v e d in plagioclases s h o w i n g t w i n n i n g a n d e x s o l u t i o n a n d in pigeonites w i t h a b e g i n n i n g e x s o l u t i o n of augite. T w i n s a c c o r d i n g to t h e " K a r l s b a d l a w " , a l b i t e law, a n d a c o m b i n e d " K a r l s b a d - a l b i t e l a w " are c o m m o n l y o b s e r v e d in t e r r e s t r i a l a n d l u n a r plagioclases. This twinnir~g is p a r t l y submicroscopic. Some l u n a r plagioclase specim e n s w i t h b y t o w n i t e c c m p o s i t i o n show a n " i n c o h e r e n t " t w o - p h a s e diffraction p a t t e r n a n d are i n t e r p r e t e d as s u b m i c r o s c o p i c a l l y interg r o w n p h a s e s w i t h different A n c o n t e n t s . D i s o r d e r effects in o r t h o p y r o x e n e s are m o s t p r o b a b l y d u e to t h e o b s e r v e d zonal s t r u c t u r e of t h e crystals. JAMES, O. B., AND W~RI~HT, T. L., 1972. Apollo 11 a n d 12 m a r e b a s a l t s a n d g a b b r o s : Classification, c o m p o s i t i o n a l v a r i a t i o n s , a n d possible p e t r o g e n e t i c relations. Geol. Soc. Amer. Bull. 83, 2357-2382. On t h e basis of c o m p o s i t i o n , it is possible to d i s t i n g u i s h t h r e e m a j o r g r o u p s of Apollo 12 b a s a l t i c rocks: olivine p i g e e n i t e basalts and gabbros, ilmenite-bearing basalts a n d g a b b r o s , a n d f e l d s p a t h i c basalts. Two m a j o r g r o u p s of Apollo 11 b a s a l t s are also distinguishable: ophitic ihnenite basalts and i n t e r s e r t a l i l m e n i t e basalts. C o m p o s i t i o n a l v a r i a t i o n s b e t w e e n s a m p l e s w i t h i n g r o u p s are g e n e r a l l y d o m i n a t e d b y MgO v a r i a t i o n s , w h e r e a s differences b e t w e e n g r o u p s are p r i m a r i l y i n v e r s e v a r i a t i o n s o f TiO2 a n d SiO2 or Al2Oa a n d FeO. R e s u l t s of f r a e t i o n a t i o n c a l c u l a t i o n s i n d i c a t e t h a t t h e MgO v a r i a t i o n t r e n d s are e x p l a i n e d p r i n c i p a l l y b y low-pressure f r a c t i o n a t i o n of e a r l y - c r y s t a l l i z e d olivine ± p i g e o n i t e ± c h r o m e spinel. T h e A120 a v e r s u s F e O t r e n d in t h e b a s a l t s m i g h t possibly b e e x p l a i n e d b y n e a r - s u r f a c e f r a c t i o n a t i o n , b u t t h e TiO 2 v e r s u s SiO2 t r e n d is n o t e x p l a i n a b l e in t h i s way. I n v e s t i g a t i o n s of t h e l a t t e r t r e n d in t e r m s of possible processes of h i g h - p r e s s u r e f r a c t i o n a l m e l t i n g or f r a c t i o n a l

MOON--SURFACE LAYER crystallization indicate that the compositional variations cannot be the products of simple variations in depth or degree of fractionation. JUAN, V. C., CHEN, J. C., HUA~G, C. K., CI-IEN, P. Y., AND WANG LEE, C. M., 1972. Petrology and chemistry of some Apollo 14 lunar samples. Geochim. Cosmochim. A cta Suppl. 3, 1, 687-705. The petrography of 14310,178; 14066,37; 14305,103; and 14313,55 and the chemistry of 14310,197 have been studied by means of optical, X ray diffraction and atomic absorption techniques. The three welded lunar breccias (14066,37, 14305,103, and 14313,55) consist essentially of lithic and mineral clasts set in a fine-grained matrix. The occurrence of pre-existing regoliths, crystalline lithic fragments, basaltic rock fragments, and chondritic lunar samples in the breecias m a y have resulted from large-scale cratering events with thick, hot ejecta blanket. The minor amounts of anorthositic fragments found in the three breccias m ay have originated from the highlands. The mechanism of base surge deposition is perhaps the best hypothesis proposed to produce thermal sintering in the welded breccias. 14310(178,197) is a fine-grained, diabasic to subophitic nonmare basalt. Its petrographic characteristics are: (1) ratio of plagioclase (highly calcic) to mafics, approximately 65:35, (2) some pigeonites are rimmed by subcalcic augites, (3) the grain size of all phases is less than l m m , (4) there are very few vugs or vesicles, and (5) the opaque minerals are in low concentrations (~2%). Sample 14310,197 has higher SiO2, A1203, Na20, K20, Rb, Sr, and Li contents and A1203/CaO, MgO/FeO, l~b/Sr and Ni/Co ratios but lower FeO, TiO2, MnO, and Cr20 a contents and N a 2 0 / K 2 0 ratio than previously analyzed lunar samples. The noritic fragments {enriched in K R E E P ) found in Apollo 12 soils chemically are similar to 14310,197. The high Si, A1, Na, K, Rb, Sr, and Li contents in 14310,197 and other Fra Mauro basalts indicate that basaltic rocks from the maria could not have been derived from materials of F r a Mauro composition by partial melting. The authors suggest t h a t 14310 m a y represent a primary lunar high-alumina basalt magma generated by a small percentage of partial melting of plagioclase-bearing peridotite at a depth of less than 200km. Primary high alumina basalt m a g m a ma y play an extremely important role in the early stage of lunar evolution, because it m a y be the parental liquid for a whole spectrum of differentiates, such as feldspathie basalts, feldspathie gabbro, and anorthosite cumulates. KAISEI~, W. A., AND BEllMAN, B. L., 1972. The average 13°Ba(n,~) cross section and the

95

origin of 131Xe on the Moon. Earth Planet. Sci. Lett. 15, 320-324. The average 13°Ba(n,y) cross section has been measured for a neutron spectrum similar to the one at the lunar surface. The large cross section obtained probably explains the anomalously high concentration of lalXe found in the lunar rocks. KING, E. A., JR., BUTLER, J. C., A1NDCARMAN, M. F., 1972. Chondrules in Apollo 14 samples and size analyses of Apollo 14 and 15 fines. Geochim. Cosmochim. A c t a S u p p l . 3, 1,673-686. Chondrules have been observed in several breccia samples and one fines sample returned by the Apollo 14 mission. The chondrules are formed by at least three different processes that appear to be related to large impacts: (1) crystallization of shock-melted spherules and droplets; (2) rounding of rock clasts and mineral grains by abrasion in the base surge; and (3) diffusion and recrystallization around clasts in hot base surge and fall-back deposits. In the case of the Apollo 14 samples, the large impact almost certainly is the Imbrian event. Some of the chondrules in chondritic meteorites m ay have formed by similar processes on other planetary surfaces. Many of the differences between petrologic types of chondritic meteorites can be accounted for by this model. Chondrules may be an inevitable result of the terminal stages of accretion of silicate planetary bodies. Grain size analyses of undisturbed fines samples from the Apollo 14 site and from the Apollo 15 Apennine Front are almost identical, indicating that the two localities have similar meteoroid bombardment exposure ages, approximately 3.7 × 109yr. This observation is consistent with the interpretation t h a t both the F r a Mauro formation and the Apennine Front material originated as ejecta from the Imbrian event. Size analyses of fines from under, on and around the boulder that was sampled near St. George Crater indicate that the boulder has been exposed at that site for a short period of time, probably less than 1 x 105yr. KLEIN, C., J m , AND DI~AKE, J. C., 1972. Mineralogy, petrology, and surface features of some fragmental material from the Fra, Mauro site. Geochim. Cosmochim. Acta Suppl. 3, 1, 1095-1113. Lithic fragments from a 1-g sample of coarse fines {14257,2) and mierobreecia 14305,4 were studied by optical, electron microprobe, and scanning electron microscope techniques. Five mineralogically and texturally distinct igneous rock fragments from the coarse fines were selected for study. These are microgabbro, olivine-ilmenite basalt, ophitic basalt, anorthosite, and norite. The basalt fragments show considerably less Fe-enrichment and zoning in single-crystal pyroxene grains than

96

AFCRL BIBLIOGRAPItY--3RD QUARTER 1972

was o b s e r v e d in t h e p y r o x e n e s o f t h e Apollo 12 basalts. T h e b a s a l t i c p y r o x e n e c o m p o s i t i o n s r a n g e f r o m p i g e o n i t e to subcalcic augite, augite, a n d f e r r o a u g i t e . T h e plagioclases r a n g e f r o m Any6 to Ang0. T h e a n o r t h o s i t e a n d n o r i t e f r a g m e n t s show s t r o n g g r a n u l a t i o n a n d s h e a r i n g of t h e plagioclase (Ans6-Ang~), reflecting t h e i m p a c t m e t a m o r p h i s m t o w h i c h m a t e r i a l s in t h e F r a M a u r o f o r m a t i o n were s u b j e c t e d . M i c r o b r e c c i a 14305,4 a n d several f r a g m e n t s of breccia in t h e coarse fines s h o w c o m p l e t e l y r e c r y s t a l l i z e d m a t r i c e s a n d t h e i r clasts e x h i b i t t h e following s h o c k a n d h e a t effects : (a) breccial i o n of s i n g l e . c r y s t a l a n d r o c k f r a g m e n t s ; (b) p a r t i a l m e l t i n g a n d r e a c t i o n zones a l o n g o u t e r edges of a n d f r a c t u r e s in single-crystM f r a g m e n t s ; (c) m i c r o f a u l t i n g in m i n e r a l g r a i n s as s h o w n b y d i s p l a c e d t w i n l a m e l l a e ; (d) dev i t r i f i c a t i o n a n d r e c r y s t a l l i z a t i o n of s p h e r o i d a l clasts, p r o b a b l y originally glass spherules. Ahnost totally gradational contacts between some rock clasts a n d t h e m a t r i x also were n o t e d . O t h e r m i c r o b r e c c i a f r a g m e n t s s h o w only partially d e v i t r i f i e d m a t r i c e s , a n d some are comp l e t e l y u n r e c r y s t a l l i z e d w i t h glass clasts a n d glass m a t r i x . I t a p p e a r s t h a t a c o m p l e t e series exists f r o m u n r e c r y s t a l l i z e d to h i g h - g r a d e m e t a m o r p h i c breccias. T h e o u t e r surfaces of several of t h e rock a n d m a n y of t h e glass fragm e n t s a n d s p h e r o i d a l bodies in t h e coarse fines show fine-scale s p a l l a t i o n f e a t u r e s a n d microc r a t e r s d u e t o t h e i m p a c t of h y p e r v e l o c i t y particles. Similar c r a t e r s o c c u r on some of t h e i r o n - n i c k e l f r a g m e n t s , w h i c h m a k e u p less t h a n 0.1 w t % of t h e coarse fines. KURAT, G., KEIL, K., PRINZ, M., AND NEHRU, C. D., 1972. C h o n d r u l e s of l u n a r origin. Geochim. Cosmochim. ActaSuppl. 3, l, 707-721. C h o n d r u l e s a n d glass s p h e r u l e s f r o m Apollo 14 breccia 14318,4 were s t u d i e d microscopically, a n d t h e i r b u l k a n d m i n e r a l c o m p o s i t i o n s were d e t e r mined with the electron microprobe. Approxim a t e l y 6 5 % of all c h o n d r u l e s are of A N T (anorthositic-noritic-troctolitic) composition w i t h all b u t one c l u s t e r i n g a r o u n d t h e comp o s i t i o n a l e q u i v a l e n t of a n a n o r t h o s i t i c norite. No A N T glass s p h e r u l e s were o b s e r v e d . K I ~ E E P a n d b a s a l t i c c h o n d r u l e s o v e r l a p in c o m p o s i t i o n a n d a b u n d a n c e w i t h K R E E P a n d b a s a l t i c glass spherules. Conclusions: (i) C h o n d r u l e s in 14318,4 are s i m i l a r in t e x t u r e to m e t e o r i t i c c h o n d r u l e s b u t differ d r a s t i c a l l y in c o m p o s i t i o n . H e n c e , t h e f o r m e r were p r o d u c e d o n t h e l u n a r surface b y i m p a c t m e l t i n g a n d s p l a t t e r i n g of l u n a r rocks of A N T , K R E E P , a n d b a s a l t i c composition. (ii) L u n a r c h o n d r u l e s f o r m e d b y s p o n t a n e o u s c r y s t a l l i z a t i o n of h i g h l y supercooled, freely floating, m o l t e n droplets. (iii) T h e

cooling r a t e s of i m p a c t p r o d u c e d m o l t e n d r o p l e t s a t Apollo 14 (large i m p a c t e v e n t s ) were g e n e r a l l y lower t h a n t h o s e of d r o p l e t s p r o d u c e d a t Apollo 11 (small i m p a c t e v e n t s ) . H e n c e , t h e p r o b a b i l i t y for h o m o g e n e o u s a n d h e t e r o g e n e o u s n u c l e a t i o n f r o m t h e supercooled s t a t e was h i g h e r a t Apollo 14 t h a n for m o s t Apollo 11 e v e n t s , r e s u l t i n g in t h e f o r m a t i o n of m a n y c h o n d r u l e s a t Apollo 14 b u t o v e r w h e l m i n g glass s p h e r u l e s a t Apollo 11. (iv) A N T ( a n o r t h o s i t i c norite) m o l t e n d r o p l e t s , for reasons of c o m p o s i t i o n , a p p e a r to be m o r e a p t to n u c l e a t e f r o m t h e s u p e r c o o l e d s t a t e , and, h e n c e , f o r m e h o n d r u l e s t h a n t h o s e of K R E E P a n d b a s a l t i c c o m p o s i t i o n . (v) T h e r e l a t i v e l y r e s t r i c t e d c o m p o s i t i o n of t h e m a i n cluster of A N T c h o n d r u l e s suggests t h a t t h e y were f o r m e d b y i m p a c t m e l t i n g a n d s p l a t t e r i n g of a r e l a t i v e l y h o m o g e n e o u s , fine-grained a n o r t h o s i t i c norite, or f r o m a c o a r s e r - g r a i n e d n o r i t e t h a t was h o m o g e n i z e d in tile i m p a c t process. (vi) T h e s i m i l a r i t y in t e x t u r e of i m p a c t p r o d u c e d l u n a r a n d m e t e o r i t i c c h o n d r u l e s suggests t h a t if m a j o r i m p a c t e v e n t s o c c u r r e d on p a r e n t m e t e o r i t e bodies, a t least some of t h e m e t e o r i t i c c h o n d r u l e s may have formed by impact melting and splattering. KUSHIRO, I., IKEDA, Y., AND NAKA~IUItA, Y., 1972. P e t r o l o g y of Apollo 14 h i g h - a l u m i n a b a s a l t . Geochim. Cosmochim. Acta Suppl. 3, 1, 115-129. Melting experiments and microprobe analyses h a v e b e e n carried o u t on t h e Apollo 14 higha l u m i n a b a s a l t 14310 (A1203 2 1 . 7 w t % w i t h M g O / F e O r a t i o h i g h e r t h a n t h o s e of t h e Apollo 11 a n d 12 c r y s t a l l i n e rocks). A n o t h e r c r y s t a l l i n e rock, 14053, a n d a breccia, 14321, h a v e b e e n a n a l y z e d w i t h t h e m i c r o p r o b e . Tile l i q u i d u s p h a s e of t h e rock 14310 is plagioelase u p to a b o u t 10kb, c h r o m i a n spinel b e t w e e n a b o u t 10 and 20kb, and pyrope-rich garnet above 20kb. T h e c o m p o s i t i o n of t h i s rock, as well as t h o s e of f e l d s p a t h i c b a s a l t s t h a t are c o n s i d e r e d to be h i g h l a n d s m a t e r i a l s , is s e p a r a t e d f r o m possible lunar "mantle" compositions by low-temperat u r e coteetic b o u n d a r i e s a t l e a s t u p to 10kb, s u g g e s t i n g t h a t t h e m a g m a s o f t h e s e rocks are n o t p r o d u c t s of d i r e c t p a r t i a l m e l t i n g of t h e l u n a r " m a n t l e " or of f r a c t i o n a l c r y s t a l l i z a t i o n of a p r i m a r y m a g m a a t l e a s t to t h e d e p t h of 3 0 0 k m u n d e r a n h y d r o u s c o n d i t i o n s . I t is m o s t p r o b a b l e t h a t t h e s e h i g h l a n d rocks were genera t e d b y p a r t i a l or b u l k m e l t i n g of a p l a g i o c l a s e c u m u l a t e rock t h a t h a d b e e n f o r m e d b y a largescale d i f f e r e n t i a t i o n in t h e shallow p a r t s of t h e l u n a r i n t e r i o r a t a n earlier stage. T h i s a r g u m e n t is v a l i d e v e n if r o c k 14310 is a p l a g i o c l a s e c u m u l a t e r o c k w i t h less t h a n 15% plagioelase e n r i c h m e n t . I f c o n s i d e r a b l e a m o u n t s (70% or m o r e ) of alkalis were lost before solidification,

MOON--SURFACE

t h e original m a g m a could h a v e b e e n f o r m e d b y d i r e c t p a r t i a l m e l t i n g of t h e l u n a r " m a n t l e " m a t e r i a l w i t h M g O / F e O r a t i o s i m i l a r t o t h a t of t h e e a r t h ' s u p p e r m a n t l e or b y f r a c t i o n a l c r y s t a l l i z a t i o n of a p r i m a r y m a g m a a t d e p t h s of about 100km. LALL¥, J. S., FISHER, 1%. U., CHRISTIE, J. M., GRIGGS, D. T., HEUER, A. H., NORD, G. L., JR., AND 1%ADCLIFFE, S. V., 1972. E l e c t r o n p e t r o g r a p h y of Apollo 14 a n d 15 rocks. Geochim. Cosmochim. Acta Suppl. 3, 1, 401 422. Comp a r a t i v e optical a n d h i g h - v o l t a g e ( 8 0 0 - 1 0 0 0 k V ) e l e c t r o n p e t r o g r a p h i c a n a l y s e s h a v e b e e n cond u c t e d o n igneous rocks a n d several t y p e s of breccias f r o m Apollo 14 a n d 15. T h e p r i n c i p a l r e s u l t s c a n b e s u m m a r i z e d as follows: Breccias: T h e m a t r i x of r o c k 14321, a l t h o u g h o p t i c a l l y isotropic, is s h o w n to consist p r i n c i p a l l y of submicroscopic crystals exhibiting highly heterogeneous d e f o r m a t i o n a n d r e c r y s t a l l i z a t i o n subs t r u c t u r e s , w h i c h are p a r t i c u l a r l y p r o m i n e n t a t g r a i n c o n t a c t s . T h e s e c h a r a c t e r i s t i c s are b e l i e v e d to result from the high pressures and temperatures accompanying the shock waves associated w i t h m e t e o r i t i c i m p a c t . I t is p r o p o s e d t h a t t h e c o h e s i o n of t h i s breccia is d u e m a i n l y t o d e f o r m a t i o n ( " p r e s s u r e w e l d i n g " ) a s s o c i a t e d w i t h rec r y s t a l l i z a t i o n ; t h i s m e c h a n i s m is t e r m e d " s h o c k s i n t e r i n g " . A n o t h e r c o m m o n l u n a r breccia, t h e glass-welded t y p e , was r e p r e s e n t e d b y t w o breccia f r a g m e n t s f r o m t h e 14161 r a k e s a m p l e . One e x t r e m e of t h i s t y p e , i n w h i c h t h e glass was t h e m a j o r c o m p o n e n t ( ~ 9 0 % ) , e x h i b i t e d s h a r p glass c r y s t a l interfaces, i n d i c a t i v e of r a p i d cooling. I n t h e o t h e r e x t r e m e , t h e glass is a m i n o r p h a s e ( ~ 1 0 % ) a n d e x i s t s as a n i n t e r c r y s t a l l i n e film, w i t h diffuse g l a s s - c r y s t a l i n t e r faces. D e s p i t e t h i s i n d i c a t i o n of slow cooling, a n u n u s u a l f e a t u r e of m a n y of t h e c r y s t a l f r a g m e n t s i n t h i s b r e c c i a w a s a h i g h d e n s i t y ( 3 - 6 x 10~°/cm 2) of fossil p a r t i c l e t r a c k s w h i c h a p p a r e n t l y s u r v i v e d t h e h e a t i n g a s s o c i a t e d w i t h consolidation. Laboratory experiments on lunar dust have e s t a b l i s h e d t h a t c o n s o l i d a t i o n c a n b e effected b y s i m p l e t h e r m a l s i n t e r i n g . H o w e v e r , n o n e of t h e l i m i t e d n u m b e r of b r e c c i a s e x a m i n e d t o d a t e e x h i b i t e d s u b s t r u c t u r e s c h a r a c t e r i s t i c of t h i s m e c h a n i s m . Crystalline Rocks: O n t h e basis of t h e p r e s e n c e of v e r y fine-scale e x s o l u t i o n a n d t h e size of t h e (b) t y p e d o m a i n s i n plagioclase, a n d on t h e scale of t h e M-T A P B s t r u c t u r e i n pigeonite, r o c k 14310 is t h o u g h t t o h a v e cooled m o r e slowly t h a n Apollo 12038 a n d 12053 b a s a l t s . A n o r t h i t e in 15415 is s o m e w h a t m o r e d e f o r m e d t h a n t h e plagioclase in Apollo 11 a n d 12 b a s a l t s a n d c o n t a i n s n u m e r o u s m i c r o t w i n s , o n w h i c h s u b m i c r o s c o p i c p y r o x e n c h a s precipit a t e d . T y p e (c) d o m a i n s t r u c t u r e s are p r e s e n t

LAYER

97

a n d are c o n s i d e r a b l y l a r g e r t h a n in l u n a r b y t o w n i t e s ; t h i s is b e l i e v e d to b e a c o n s e q u e n c e of t h e h i g h A n ( ~ 9 5 % ) c o n t e n t . LEVY, C., CHRISTOI'tIE-MICHEL -LEVY, M., PICOT, P., AND CAYE, 1%., 1972. A n e w t i t a n i u m a n d z i r c o n i u m oxide f r o m t h e Apollo 14 s a m p l e s . Geochim. Cosmochim. Acta Suppl. 3, 1, 1 1 1 5 1120. T h i s n e w p h a s e w a s f o u n d in fines 14003,47. I t s c h e m i c a l c o m p o s i t i o n is e s s e n t i a l l y t h a t of a n a r m a l c o l i t e , a l t h o u g h t h e p h y s i c a l p r o p e r t i e s are different. I t s f o r m u l a is g i v e n b e l o w : Ti1.91Zro.osFeo.27Mgo.loCro.2sAlo.ovCao.12Sio.o2Os. I t h a s b e e n o b s e r v e d in a p o l i s h e d section as a n o p t i c a l l y isotropic surface 30/xm across s u r r o u n d ed b y ilmenite. T h e r e f o r e n o X r a y crystallog r a p h i c a l s t u d y h a s b e e n possible. N e v e r t h e l e s s , t h e d i s p e r s i o n c u r v e of its reflectivities (from 400 to 7 0 0 n m ) differs sufficiently in its s h a p e a n d b y its a b s o l u t e r e f l e c t i v i t y v a l u e s f r o m t h a t of a r m a l c o l i t e to i n d i c a t e t h a t we are d e a l i n g w i t h a different phase. LIPSKII, YU. N., AND SHEVCHElgKO, V. V., 1972. P r e p a r a t i o n of a s p e c t r o z o n a l m a p for a n a r e a on t h e l u n a r surface. Sov. A s t r o n . ~ A J 16, 132-136. F r o m s p e c t r o z o n a l p h o t o g r a p h s of t h e m o o n t a k e n a t effective w a v e l e n g t h s of 380 a n d 640m/z, a c o n t o u r m a p h a s b e e n p r e p a r e d for t h e " r e d d e n i n g coefficient" /~ = PR/pu in t h e M a r e I m b r i u m region. T h e Soviet C o m p l e t e M a p of t h e M o o n p r o v i d e s t h e t o p o g r a p h i c d a t a . A r e a s of different color are f o u n d t o b e c o r r e l a t e d w i t h c e r t a i n relief features. T h e c o l o ~ a l b e d o r e l a t i o n h a s a c o m p o u n d form, w i t h t w o b r a n c h e s corresponding to mare terrain and postmare crater formations. LONGttI, J., WALKER, D., AND HAYS, J . F., 1972. P e t r o g r a p h y a n d c r y s t a l l i z a t i o n h i s t o r y of b a s a l t s 14310 a n d 14072. Geochim. Cosmoehim. Acta Suppl. 3, 1, 131 139. R o c k 14310 is a h i g h a l u m i n a b a s a l t c o n t a i n i n g plagioelase p h e n o crysts, g r a i n s of p i g e o n i t e w i t h o r t h o p y r o x e n e cores, a n d a p a r t i a l l y u n m i x e d glassy r e s i d u u m . R o c k 14072 is a s u b o p h i t i c b a s a l t w i t h large r e s o r b e d olivine p h e n o e r y s t s . B o t h rocks s h o w e v i d e n c e for s t r o n g p o s t e r y s t a l l i z a t i o n r e d u c t i o n . C o n s i d e r a t i o n of F e / M g in plagioclase a n d o t h e r c o m p o s i t i o n a l a n d t e x t u r a l e v i d e n c e leads t o a r e j e c t i o n of t h e a l k a l i - v o l a t i l i z a t i o n h y p o t h e s i s . LOVERING, J . F., WARK, D. A., GLEADOW, A. J . W . , AND SEWELL, D. K . B., 1972. U r a n i u m a n d p o t a s s i u m f r a c t i o n a t i o n in p r e - I m b r i a n l u n a r c r u s t a l rocks. Geochim. Cosmochim. Acta Suppl. 3, 1, 281-294. U r a n i u m a n d p o t a s s i u m a b u n d a n c e d a t a f r o m rock clasts in r e c r y s t a l l i z e d Apollo 14 breccia 14305 i n d i c a t e t h a t t h r e e uranium-potassium fraetionation groups can be

98

AFCRL B I B L I O G R A P t t Y - - 3 R D QUARTER 1972

r e c o g n i z e d : Group 1. L o w U ( < 0 . 5 p p m ) , low K ( < 0 . 3 % ) , c o m p o s e d of m a r e - t y p e b a s a l t s (subg r o u p A) a n d a n o r t h o s i t e s ( s u b g r o u p B). Group 2. M e d i u m U (~1.6 4 . 8 p p m ) , m e d i u m K (~0.4-2.3°/o), c o m p o s e d of n o n m a r e t y p e b a s a l t s a n d " n o r i t e s " . Group 3. H i g h U ( ~ 5 - 1 2 p p m ) , h i g h K ( ~ 3 . 9 - 6 . 2 % ) , c o m p o s e d of " m o n z o n i t i c " rockt~ ( s u b g r o u p A) a n d glasses ( s u b g r o u p B) p r o b a b l y d e r i v e d f r o m 3A rocks. This r o c k a s s o c i a t i o n is s u g g e s t e d to be t y p i c a l of t h e n e a r - s u r f a c e c r u s t of t h e m o o n in p r e - I m b r i a n t i m e a (i.e., >3.9 × 109 y e a r s ago) a n d shows m a r k e d similarities to rock associations charact e r i s t i c of P r e c a m b r i a n m a s s i f - t y p e a n o r t h o s i t e terrains on earth. MALYSHEVA, T. V., 1972. MOssbauer spectrosc o p y of l u n a r r e g o l i t h r e t u r n e d b y t h e a u t o m a t i c s t a t i o n L u n a 16. Geochim. Cosmoch#a. Acta Suppl. 3, 1, 105-114. B u l k f r a c t i o n s of h m a r r e g o l i t h f r o m t h e surface l a y e r (A) a n d t h e deeps e a t e d l a y e r (B) h a v e been m e a s u r e d for t h e n u c l i d e F e s7 b y t h e m e t h o d of M 6 s s b a u e r s p e c t r o s c o p y . Troilite, m e t a l l i c iron, ilmenite, olivine, p y r o x c n e (mostly augite), a n d glasses have been detected. Iron distribution among the mineral phases demonstrates that the regolith o f L u n a 16 differs f r o m t h e r e g o l i t h of Apollo l l b y lesser i l m e n i t e c o n t e n t a n d g r e a t e r olivine c o n t e n t . T h e L u n a 16 s a m p l e differs f r o m t h e r e g o l i t h of Apollo 12 b y slightly g r e a t e r olivine c o n t e n t . W i t h i n t h e limits of t h e a n a l y t i c a l errors, t h e m e t a l l i c iron does n o t c o n t a i n nickel. No a p p r e c i a b l e a m o u n t of iron in t h e t r i v a l e n t state has been detected. MASON, B., 1972. L u n a r t r i d y m i t e a n d c r i s t o b a l i t e . Amer. Mineral. 57, 1530 1535. T r i d y m i t e a n d e r i s t o b a l i t e in l u n a r b a s a l t 15085 a r e b e t t e r t h a n 9 9 % SiO2; t h e y c o n t a i n small p e r c e n t a g e s of TiO2 (0.38, 0.28), A1203 (0.18, 0.34), K 2 0 (0.17, 0.26), a n d N a 2 0 (0.05, 0.05). T h e a p p r o x i m a t e e q u i v a l e n c e of A1 to K + N a i n d i c a t e s s u b s t i t u t i o n of t h e t y p e KA1 = Si, t h e large c a t i o n s b e i n g a c c o m m o d a t e d in l a t t i c e vacancies. MASON, B., JAROSEWlCH, E., Mn~SON, W. G., AND THOMPSON, G., 1972. Mineralogy, petrology, a n d c h e m i c a l c o m p o s i t i o n of l u n a r samples 15085, 15256, 15271, 15471, 15475, 15476, 15535, 15555, a n d 15556. Geochim. Cosmochim. Acta Suppl. 3, 1,785-796. Chemical a n a l y s e s h a v e b e e n m a d e of s e v e n Apollo 15 rocks a n d one s a m p l e o f Apollo 15 fines. T h e rocks, all of m a r e b a s a l t c o m p o s i t i o n , r a n g e f r o m o l i v i n e - n o r m a t i v e to s l i g h t l y q u a r t z - n o r m a t i v e compositions, a n d v a r y c o n s i d e r a b l y in g r a i n size a n d t e x t u r e . T h e p r i n c i p a l m i n e r a l s in all o f t h e m are plagioclase ( a v e r a g e Ango) a n d p y r o x e n e s (pigeonite a n d augite). Most o f t h e rocks c o n t a i n some olivine;

t h e q u a r t z - n o r m a t i v e ones c o n t a i n n o olivine, b u t h a v e accessory t r i d y m i t e a n d / o r cristobalite. T h e b a s a l t s f r o m t h e edge of H a d l e y Rille (15535, 15555, 15556) a p p e a r r e l a t e d to one a n o t h e r b y olivine f r a e t i o n a t i o n , w h e r e a s t h o s e f r o m D u n e C r a t e r (15475, 15476) r e p r e s e n t a c'ompositionally d i s t i n c t flow or flows. A r o c k f r o m t h e A p e n n i n e F r o n t (15256) c o m p o s i t i o n ally is similar to t h e m a r e basalts, b u t is a h e t e r o g e n e o u s welded breccia, p r e s u m a b l y forme d b y i m p a c t on t h e m a r e surface a n d e j e c t e d to its F r o n t site. T h e m a j o r - e l e m e n t c o m p o s i t i o n of t h e fines a t D u n e C r a t e r (1547l) c a n b e closely a p p r o x i m a t e d b y a m i x t u r e of 7 0 % local basalt and 30% troctolite, suggesting that t r o c t o l i t e m a y be a n i m p o r t a n t c o n s t i t u e n t of t h e p r e - I m b r i a n crust. MASSO~', C. R., SMITH, I. B., JAMIESON, W. D., McLAcHLAN, J . L., AND VOLBORTH, A., 1972. Chromatographic and mineralogical study of Apollo 14 fines. Geochim. Cosmochim. Acta Suppl. 3, 1, 1029-1036. T r i m e t h y l s i l y l a t i o n of' h m a r fines f r o m Apollo 14 a n d c h r o m a t o g r a p h i c s e p a r a t i o n of t h e p r o d u c t s r e v e a l e d t h e trim e t h y l s i l y l d e r i v a t i v e s of t h e ions SiO~-, Si2Ov6-, a n d SiaO1So. T h e d e r i v a t i v e of t h e cyclic ion Si40 s - b a r e l y was d e t e c t a b l e , in c o n t r a s t w i t h results for Apollo 11 a n d 12 fines. D e r i v a t i v e s of h i g h e r a n i o n s were n o t d e t e c t e d in c h r o m a t o g r a m s a t t e m p e r a t u r e s as h i g h as 280°C. T h e yield a n d c h r o m a t o g r a p h i c p a t t e r n for Apollo 14 fines was c o n s i s t e n t w i t h t h e p r e s e n c e of a p p r o x i m a t e l y 7°/. olivine, as e s t a b l i s h e d b y m o d a l analysis. V o l u m e perc e n t a g e s of t h e m a i n m i n e r a l c o n s t i t u e n t s in s a m p l e s 14003,27 a n d 14163,70 were similar, as determined by point counting. These samples c o n t a i n less p y r o x e n e a n d fewer o p a q u e m i n e r a l s b u t m o r e glass a n d m a n y m o r e m e t a l l i c o p a q u e b e a d s t h a n t h e Apollo 12 s a m p l e s e x a m i n e d p r e v i o u s l y . T h e n u m b e r of glass spheres, t e a r drops, a n d d u m b b e l l - s h a p e d o b j e c t s p e r millig r a m is of t h e s a m e o r d e r as in t h e Apollo 12 fines. As in p r e v i o u s work, t h e r a t i o of i n t e g r a t e d p e a k areas Si207/SiO4 d u e to t h e d i m e r i c a n d m o n o m e r i c d e r i v a t i v e s was s l i g h t l y h i g h e r for t h e l u n a r fines t h a n could be a c c o u n t e d for b y side r e a c t i o n s in t h e t r i m e t h y l s i l y l a t i o n of olivine alone. T h e difference m a y b e d u e p a r t l y to t h e o t h e r c o n s t i t u e n t s in t h e fines a n d / o r t h e presence of v e r y s m a l l q u a n t i t i e s of d i m e r i c (e.g., m e l i l i t e g r o u p ) m i n e r a l s in t h e l u n a r m a t e r i a l . O f i n t e r e s t in t h i s c o n n e c t i o n is t h e p r e s e n c e in s a m p l e 14003,27 of some u n i a x i a l - n e g a t i v e a n d -positive g r a i n s w i t h low b i r e f r i n g e n c e a n d r e f r a c t i v e i n d e x a n d c l e a v a g e c h a r a c t e r i s t i c of such minerals. McColtD, T. B., CHARETTE, M. P., JOHNSON,

M O O ~ - - S U R F A C E LAYER T. V., LEBOFSKY, L. A., AND PIETERS, C., 1972. S p e c t r o p h o t o m e t r y (0.3 to 1.1/~) of visited and proposed Apollo lunar landing sites. The Moon 5, 52 89. This p a p e r discusses a s t u d y of the spectral reflectance of regions of the lunar surface containing m o s t of t h e proposed Apollo landing sites. Using these measurements, inform a t i o n regarding surface properties such as composition and mineralogy can be obtained. Specifically ( 1 ) t h e presence of p y r o x e n e s which cause an absorption b a n d near 0.95/~ in t h e l u n a r reflection s p e c t r u m ; (2) t h e proportion of crystalline to glassy material present in the soil which is d e r i v e d from the slope of the refiectivity curve between 0.4/~ and 0.7tL and s t r e n g t h of the 0.95~ absorption b a n d ; (3) the presence of Ti 3+ ions in t h e glasses on the lunar surface which effects t h e reflection s p e c t r u m at blue and ultraviolet wavelengths. The s t u d y uses inform a t i o n gained by analysis of t h e spectral properties of lunar samples in the l a b o r a t o r y and telescope spectra of over 100 lunar areas to p r o v i d e information regarding t h e composition and mineralogy of each proposed lunar landing site. McCuE, J . J. G., AND CROCKEI~, E. A., 1972. L u n a r reflectivity at 0.86-centimeter wavelength. J. Geophys. Research 77, 4069-4078. B a c k s c a t t e r i n g of 0.86-cm circularly polarized radiation by 29 regions on the m o o n has been m e a s u r e d w i t h b e t t e r signal-to-noise ratio t h a n was available heretofore. B o t h circular polarizations were received. At a given angle of incidence, power received in the " e x p e c t e d " polarization was greater for t h e highland regions t h a n for t h e seas, b y roughly l db. F o r m o d e r a t e l y large angles of incidence, ¢, this r e t u r n diminishes more rapidly t h a n c o s ¢ , t h o u g h perhaps n o t as rapidly as it does at longer wavelengths. The cross section of the whole m o o n is 5 ± 2 0 of t h e geometric cross section; a b o u t 80% of t h e cross section is ascribable to diffuse scattering. The polarization ratio for the echoes varies s m o o t h l y with t h e angle of incidence, from 0.7 at t h e s u b r a d a r point to 0.4 at 70 °. The depolarization is t h e same for marial and h i g h l a n d regions, and at large angles of incidence it is t h e same as has been found at 2 3 e m and 6 8 c m b y o t h e r workers. McKA~, D. S., CLANTO~, U. S., MORRmON, D. A., AND LADLE, G. H., 1972. V a p o r phase crystallization in Apollo 14 breccia. Geochim. Cosmochim. Acta Suppl. 3, l, 739-752. M a n y of the highly recrystallized breccias from Apollo 14 contain vugs with well-developed crystals of plagioelase, pyroxene, ilmenite, apatite, whitlockite, iron, nickel-iron, and troilite t h a t e x t e n d f r o m the v u g walls and bridge open spaces.

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These crystals are interpreted as h a v i n g f o r m e d by deposition from a h o t v a p o r containing oxides, halides, sulfides, alkali metals, iron, a n d possibly other chemical species. The hot v a p o r was associated w i t h t h e t h e r m a l m e t a m o r p h i s m and subsequent cooling of t h e F r a Mauro formation after it had been deposited as an ejecta blanket by the I m b r i a n impact. The cooling of hot lunar ejecta blankets resemble t h e cooling of terrestrial ash flows t h a t c o m m o n l y h a v e had vapor-phase crystallization in cavities. R e d i s t r i b u t i o n of volatile species in a v a p o r phase appears to be a significant feature of large lunar ejecta blankets, and m a y h a v e been m o r e i m p o r t a n t in early lunar history w h e n late stage accretion and mare basin e x c a v a t i o n p r o v i d e d v e r y large ejecta blankets. McKAY, D. S., HEIKEN, G. H., TAYLOR, R. M., CLANTON, U. S., MORttISON, D. A., AND LADLE, G. H., 1972. Apollo 14 soils : Size distribution and particle types. Geochim. Cosmochim. Acta Suppl. 3, 1,983-994. E l e v e n soil samples from Apollo 14 h a v e been studied by sieving and petrographic m e t h o d s for sizes down to a b o u t 1 t~m. A v e r a g e m e a n grain size (Mz) of the less t h a n 1 m m size fraction is 3.62¢ (81/~m) w i t h a sorting v a l u e (al) of 2.06¢. Most of the Apollo 14 soils are slightly coarser and more poorly sorted t h a n soil from the Apollo 11 and 12 landing sites. A graphic m e a n grain size of a b o u t 4.08¢ (60/~m) m a y represent an equilibrium grain size at which destruetional processes are balanced b y constructional processes. Agglutinates are the p r i m a r y p r o d u c t of constructional processes in t h e l u n a r soil. T h e y are produced for the m o s t p a r t b y m e l t i n g during m i c r o m e t e o r i t e impacts. Most of t h e glass p r o d u c e d on the lunar surface is in t h e form of agglutinates. Soil from t h e " s m o o t h t e r r a i n " at the Apollo 14 site contains a b u n d a n t agglutinates {as m u c h as 60% of some size fractions) and is low in breccia fragm e n t content. Cone Crater soil is low in agglutinates and has t h e highest recrystallized breccia c o n t e n t (94%) of any of the Apollo 14 soil samples. I t is p r o b a b l y the most r e p r e s e n t a t i v e sample of t h e deeper parts of the F r a Mauro formation, which suggests t h a t these zones consist m a i n l y of recrystallized breccia. Me,FAT, P. H., 1972. A p e r t u r e synthesis p o l a r i m e t r y of the Moon at 21 cm. M. N. R. A. S. 160, 139-154. The a u t h o r presents a p e r t u r e synthesis m a p s of the Moon's polarized t h e r m a l radio emission at 1420MHz which h a v e a resolution of 47 : arc in right ascension b y 105 ~ arc in declination. The m e t h o d by which t h e m o t i o n of t h e Moon was t a k e n into account, which i n v o l v e d performing an inverse F o u r i e r t r a n s f o r m on v e r y irregularly sampled data, is

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AFCRL B I B L I O G R A P H Y - - 3 R D QUARTER 1 9 7 2

o u t l i n e d . A simple m o d e l of t h e emission w h i c h a s s u m e s a dielectric c o n s t a n t of 2.8, a G a u s s i a n d i s t r i b u t i o n of surface slopes w i t h a s t a n d a r d d e v i a t i o n of 10 °, a n e q u a t o r i a l t e m p e r a t u r e of 2 2 4 ° K a n d a p o l a r cooling p r o p o r t i o n a l to cos °'z (latitude) gives a good d e s c r i p t i o n of t h e emission. T h o u g h local d e v i a t i o n s in l i m b b r i g h t e n i n g a n d p o l a r i z a t i o n arc f o u n d , t h e y are n o t c o r r e l a t e d w i t h sea or h i g h l a n d areas. T h e m e a n t e m p e r a t u r e difference b e t w e e n sea a n d h i g h l a n d regions is n o t g r e a t e r t h a n 5°K. MUAN, A., HAUCK, J., AND LOFALL, W., 1972. Equilibrium studies with a bearing on lunar rocks. Geochim. Cosmochim. Acta Suppl. 3, l , 185 196. E q u i l i b r i u m s t u d i e s of l u n a r rocks a n d o f s y n t h e s i z e d oxide a n d silicate p h a s e s h a v e b e e n carried o u t in t h e t e m p e r a t u r e r a n g e of 1000-1400°C u n d e r s t r o n g l y r e d u c i n g c o n d i t i o n s a t a t o t a l p r e s s u r e of 1 a r m . L i q u i d u s a n d solidus t e m p e r a t u r e s a n d s e q u e n c e of a p p e a r a n c e of c r y s t a l l i n e p h a s e s were d e t e r m i n e d for t h e two l u n a r r o c k s 14310 a n d 14259. T h e f o r m e r h a s a l i q u i d u s t e m p e r a t u r e of a p p r o x i m a t e l y 1285°C w i t h plagioclase as t h e p r i m a r y c r y s t a l l i n e phase, a n d a solidus t e m p e r a t u r e of a p p r o x i m a t e l y ll20°C. The latter sample has a liquidus temp e r a t u r e of a p p r o x i m a t e l y 1232°C, a g a i n w i t h plagioclase as t h e p r i m a r y c r y s t a l l i n e phase, a n d a solidus t e m p e r a t u r e of a p p r o x i m a t e l y l l 3 0 ° C . S t u d i e s of s y n t h e s i z e d m i x t u r e s were c o n c e n t r a t e d in t w o m a i n areas, one d e a l i n g w i t h s u b s o l i d u s r e l a t i o n s in t i t a n a t e a n d spinel phases, t h e o t h e r w i t h l i q u i d u s p h a s e r e l a t i o n s in simplified iron silicate s y s t e m s . E q u i l i b r i u m r e l a t i o n s in t h e s y s t e m F e O A12Oa-TiO e a t 1300°C were e s t a b l i s h e d , s h o w i n g t h e existence of a m i s c i b i l i t y gap in t h e Fe2TiO4-FeAleO4 solid-solution series. A similar spinel m i s c i b i l i t y g a p is p r e s e n t in t h e s y s t e m MgO A12Oa-TiO e a t 1300°C, w h e r e a s a c o n t i n u o u s spinel solids o l u t i o n series is p r e s e n t a t 1400°C. I n e a c h of t h e s y s t e m s Mg2TiO4-MgAleO4-MgCr204 a n d F e 2T i O 4 - F e A 1 2 0 4 - F e C r 2 0 4 , a t t e m p e r a t u r e s in t h e r a n g e of 1000 1300°C, a m i s c i b i l i t y g a p o r i g i n a t e s a l o n g t h e t i t a n a t e - a l u m i n a t e join a n d e x t e n d s p a r t - w a y t o w a r d t h e c h r o m i t e e n d of t h e diag r a m . T h e m o d e l iron silicate s y s t e m CaMgSieO6FeeSiOg-CaA1Si2Os, d i s p l a y s p h a s e r e l a t i o n s i n v o l v i n g t h e coexistence of liquids w i t h olivine, p y r o x e n e , a n o r t h i t e , or spinel a t t e m p e r a t u r e s s i m i l a r to t h o s e of t h e liquidus-solidus r a n g e o b s e r v e d in l u n a r rocks (~1100 1300°C). tb NELEN, J., NOONAN, A., AND FREDRIKSSON, K., 1972. L u n a r glasses, breecias, a n d c h o n d r u l e s . Geochim. Cosmochim. Acta Suppl. 3, 1, 723-737. Glasses f r o m Apollo 11, 12, 14, a n d 15 soil s a m p l e s h a v e b e e n g r o u p e d on t h e basis of t h e i r c h e m i s t r y a n d a p p e a r to p r o v i d e a n i n d e p e n d e n t

tool for i d e n t i f y i n g t h e p r e s e n c e of v a r i o u s r o c k types. T h e glasses also a p p e a r to c o n s t i t u t e a r e c o r d of c o m p l e x d i f f e r e n t i a t i o n processes t h a t seem to h a v e t a k e n place w i t h i n t h e m o o n . A g r e e n glass, a b u n d a n t in some s a m p l e s f r o m H a d l e y Delta, could h a v e b e e n f o r m e d f r o m a p r e v i o u s l y p r o p o s e d d i f f e r e n t i a t i o n model. F o u r breecias are d e s c r i b e d briefly a n d c e r t a i n similarities b e t w e e n i m p a c t features, i n c l u d i n g c h o n d r u l e s , in l u n a r s a m p l e s a n d m e t e o r i t e s are noted. NOVe'ATZKI, E . A., 1972. T h e effect of a t h e r m a l and ultrahigh vacuum environment on the s t r e n g t h of p r e c o m p r e s s e d g r a n u l a r m a t e r i a l s . The Moon 5, 31-40. A t t e n u a t i o n of seismic w a v e s in t h e M o o n ' s c r u s t a l - z o n e is e x t r e m e l y low r e l a t i v e to t h a t in t y p i c a l surface m a t e r i a l s on E a r t h a n d in l u n a r m a t e r i a l s t e s t e d u n d e r terrestrial environmental conditions. Low a t t e n u a t i o n of seismic e n e r g y in h e t e r o g e n e o u s g r a n u l a r m a t e r i a l s is u n u s u a l b e c a u s e such m a t e r i a l s h a v e a n i n h e r e n t p r o p e n s i t y to dissipate e n e r g y t h r o u g h p a r t i c l e slippage. This suggests t h a t in tile h i s t o r y of t h e M o o n ' s f o r m a t i o n t h e r e m a y h a v e b e e n processes a c t i n g t h a t h a v e a l t e r e d some of t h e b u l k p r o p e r t i e s one w o u l d e x p e c t f r o m a h e t e r o g e n e o u s assemblage of particles of t h e M o o n ' s p a r e n t m a t e r i a l . T h e a u t h o r shows t h a t l o a d i n g h i s t o r y a n d t h e e n v i r o n m e n t a l influence of h e a t a n d u l t r a h i g h v a c u u m affect t h e u n c o n f i n e d c o m p r e s s i v e s t r e n g t h of a h e t e r o g e n e o u s m a s s of g r a n u l a r m a t e r i a l . Since t h e results of t h i s s t u d y s u p p o r t t h e h y p o t h e s i s t h a t seismic e n e r g y losses d u e to slippage b e t w e e n g r a n u l a r particles m a y be negligible on t h e Moon, t h e y c o n t r i b u t e to tile d e v e l o p m e n t of a n e n e r g y flow m o d e l t h a t helps to e x p l a i n t h e a n o m a l o u s seismic r e s p o n s e of tile Moon n o t e d b y L a t h a m a n d his group. O'NIONS, R. K., AND PANKHU~ST, R. J., 1972. A 4.3 a e o n p r e - I m b r i u m e v e n t . Nature 237, 446-447. A c r y s t a l l i z a t i o n e v e n t a t 4.31 ± 0.04 a e o n r e p r e s e n t s t h e earliest igneous a c t i v i t y o n t h e M o o n d a t e d so far, a n d is e v i d e n c e for t h e age of p r e - I m b r i u m rocks. T h e I m b r i u m i m p a c t e v e n t is d a t e d a t a p p r o x i m a t e l y 3.9 a e o n b y R b Sr i n t e r n a l isochrons a n d 4°Ar/agAr ages of Apollo 14 rocks. T h e a u t h o r s r e j e c t t h e c o n t r o l of t h e R b - S r s y s t e m a t i e s of l u n a r b a s a l t whole rock s a m p l e s b y c o n t a m i n a t i o n w i t h a n R b e n r i c h e d c r u s t f o r m e d e i t h e r 4.6 or 4.3 a e o n s ago a n d suggest t h a t Apollo 14 m a g m a s were f o r m e d e i t h e r b y differing degrees of p a r t i a l m e l t i n g w i t h Sr-isotope e q u i l i b r a t i o n t h r o u g h o u t t h e source, or b y e x t e n s i v e f r a c t i o n a t i o n of a single m a g m a . A l i g n m e n t of 3.6 a e o n Apollo t 1 l o w - K a n d 3.2 a e o n Apollo 12 b a s a l t s o n a 4.56±0.34 a e o n t h r o u g h B A B I records a

MOON--SURFACE LAYER p r i m a r y d i f f e r e n t i a t i o n e v e n t , a l t h o u g h t h e age is s t a t i s t i c a l l y i n d i s t i n g u i s h a b l e f r o m t h a t of c r y s t a l l i z a t i o n of t h e Apollo 14 b a s a l t s . T h e p r e s e r v a t i o n of t h i s r e c o r d t h r o u g h l a t e r m e l t i n g e v e n t s is e x p l a i n e d b y lack of significant l i q u i d f r a c t i o n a t i o n (with r e s p e c t t o R b a n d Sr) following e i t h e r R a y l e i g h m e l t i n g , or else p a r t i a l m e l t i n g in w h i c h t h e m e l t h a s t h e s a m e R b / S r a n d STSr/S6Sr r a t i o as t h e source. PAI, S. I., HSIEH, T., AND O'KEEFE, J. A., 1972. L u n a r a s h flows: I s o t h e r m a l a p p r o x i m a t i o n . J. Geophys. Res. 77, 3631-3649. T h e a s h flow m e c h a n i s m is p r o p o s e d as one o f t h e m a j o r processes r e q u i r e d t o a c c o u n t for some f e a t u r e s o f l u n a r soil. F i r s t t h e o b s e r v a t i o n a l b a c k g r o u n d a n d t h e g a r d e n i n g h y p o t h e s i s are reviewed, a n d t h e s h o r t c o m i n g s of t h e g a r d e n i n g h y p o t h e s i s arc shown. T h e n a general d e s c r i p t i o n of t h e l u n a r a s h flow is given, a n d a simple m a t h e m a t i c a l m o d e l of t h e i s o t h e r m a l l u n a r a s h flow is w o r k e d o u t w i t h n u m e r i c a l e x a m p l e s t o show t h e differences b e t w e e n t h e l u n a r a n d t h e t e r r e s t r i a l a s h flow. T h e i m p o r t a n t p a r a m e t e r s of t h e a s h flow process are i s o l a t e d a n d a n a l y z e d . I t a p p e a r s t h a t t h e l u n a r surface l a y e r in t h e m a r i a is n o t a r e s i d u a l m a n t l e r o c k (regolith) b u t a series of a s h flows due, a t l e a s t in p a r t , to g r e a t m e t e o r ite i m p a c t s . T h e possibility of a v o l c a n i c c o n t r i b u t i o n is n o t e x c l u d e d . Some f u r t h e r a n a l y t i c r e s e a r c h o n l u n a r a s h flows is recommended. PAVICEVIC, M., RAMDOItR, P., AND EL GORES¥, A., 1972. E l e c t r o n m i c r o p r o b e i n v e s t i g a t i o n s of t h e o x i d a t i o n s t a t e s of F e a n d Ti in i l m e n i t e in Apollo 11, Apollo 12, a n d Apollo 14 c r y s t a l l i n e rocks. Geochim. Cosmochim. Acta Suppl. 3, 1, 295-303. T h e L s p e c t r a of iron a n d t i t a n i u m in m e m b e r s of t h e b i n a r y s y s t e m s i l m e n i t e - h e m a t i t e a n d u l v 6 s p i n e l - m a g n e t i t e were studied using electron microprobe techniques. I n c o m p o u n d s of a b i n a r y s y s t e m t h e F e L~/L~ r a t i o decreases u p o n increase of t h e t o t a l a m o u n t of F e 3+. C a l i b r a t i o n c u r v e s for t h e La/L ~ r a t i o a t v o l t a g e s b e t w e e n 2 a n d 2 5 k V are c o n s t r u c t e d for q u a n t i t a t i v e d e t e r m i n a t i o n of t h e o x i d a t i o n s t a t e of Fe. B y a p p l y i n g s u c h variation curves to ilmenites from the lunar s a m p l e s 10047, 12063, a n d 14053, i t w a s f o u n d t h a t F e in t h e s t u d i e d l u n a r i l m e n i t e s is p r e s e n t as F e z+. T h e Ti L s p e c t r u m of i l m e n i t e consists of t h r e e m a i n b a n d s : A, B, a n d C. T h e s e b a n d s c a n b e e x p l a i n e d o n t h e basis of t h e m o l e c u l a r o r b i t a l t h e o r y . B a n d B is d u e m a i n l y to t r a n s i t i o n s f r o m t h e 2t2g m o l e c u l a r o r b i t a l level t o t h e 2/) 3/2, w h e r e a s b a n d C is d u e t o t r a n s i t i o n s f r o m 2t2g m o l e c u l a r o r b i t a l level t o 2p ~12. B a n d A is f o r m e d m a i n l y b y t r a n s i t i o n s f r o m t h e 2% m o l e c u l a r o r b i t a l level t o 2p 3/z. T h e p r e s e n c e of

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one e l e c t r o n in t h e 2t2g (in Ti 3+) level will cause a n increase in t h e i n t e n s i t i e s of b o t h b a n d s B a n d C c o m p a r e d t o b a n d A. T h e Ti L s p e c t r a o f i l m e n i t e s in t h e l u n a r s a m p l e s 10047 a n d 12063 are i d e n t i c a l t o t h e s p e c t r u m of p u r e F e T i O 3 i n d i c a t i n g t h a t Ti i n t h o s e flmenites is p r e s e n t in t h e t e t r a v a l e n t s t a t e . I n s a m p l e 14053 t h e Ti L s p e c t r a for i h n e n i t e were f o u n d to show significant increase in t h e i n t e n s i t i e s of b a n d s B a n d C. T h i s f e a t u r e is i n t e r p r e t e d as d u e to t h e p r e s e n c e of some Ti 3+ i n t h e s t r u c t u r e of t h e i l m e n i t e of t h i s sample. POLLACK, J . B., AND WHITEttILL, L., 1972. A m u l t i p l e - s c a t t e r i n g m o d e l of t h e diffuse comp o n e n t of l u n a r r a d a r echoes. J. Geophys. Res. 77, 4289-4303. T h e a u t h o r s p r o p o s e t h a t t h e a v e r a g e diffuse c o m p o n e n t of l u n a r r a d a r echoes r e s u l t s f r o m t h e c u m u l a t i v e effect of m u l t i p l e s c a t t e r i n g w i t h i n t h e e j e c t a b l a n k e t of f r e s h y o u n g craters. U s i n g a m u l t i p l e - s c a t t e r i n g polarization computer program, they compare t h e i r m o d e l w i t h a v a r i e t y of o b s e r v a t i o n s of t h e diffuse c o m p o n e n t a n d find a general a g r e e m e n t b e t w e e n t h e two. T h e a u t h o r s show t h a t m u l t i p l e s c a t t e r i n g m a k e s a significant c o n t r i b u t i o n to t h e p a r t i a l d e p o l a r i z a t i o n of i n c i d e n t c o m p l e t e l y polarized r a d a r signals, a l t h o u g h single s c a t t e r i n g m a y also b e i m p o r t a n t . M e a n indices of r e f r a c t i o n of 1.3 a n d 1.6 are i n f e r r e d for t h e c j c c t a b l a n k e t a t w a v e l e n g t h s of 3.8 a n d 2 3 c m , r e s p e c t i v e l y . T h e s e v a l u e s are c o n s i s t e n t w i t h m e a s u r e m e n t s m a d e o n a n Apollo 11 fine s a m p l e a n d i n d i c a t e a n i n c r e a s i n g d e n s i t y w i t h d e p t h below t h e surface. T h e y h y p o t h e s i z e t h a t t h e difference b e t w e e n t h e diffuse reflectivities o f m a r e a n d h i g h l a n d a r e a s is d u e chiefly to differences b e t w e e n t h e m i c r o w a v e a b s o r p t i o n p r o p e r t i e s of r o c k s a n d d u s t in t h e two regions. I f t h a t is so, r a d a r m a p s , p r o p e r l y p r e p a r e d t o d i s p l a y s u c h differences, c a n serve as geological m a p s of t h e m i n e r a l or m i n e r a l s ( p e r h a p s i h n e n i t e ) t h a t are t h e p r i n c i p a l microwave absorbers. POWELL, S . 1~., AND WEIBLEN, P. W., 1972. P e t r o l o g y a n d origin of lithic f r a g m e n t s i n t h e Apollo 14 regolith. Geochim. Cosmochim. Acta Suppl. 3, 1, 837-852. A s y s t e m a t i c p a r t i c l e - b y p a r t i c l e s t u d y of Apollo 14 soil s a m p l e s e s t a b lished six b r o a d g r o u p s of lithic p a r t i c l e t y p e s , i n c l u d i n g : (A) p r i m a r y igneous b a s a l t s ; (B) m i c r o b r e c c i a s a n d glass-rich p a r t i c l e s of m a r e b a s a l t affinity; (C) f e l d s p a t h i c m i c r o b r e c c i a s , including related anorthosites, norites, troctolites ( A N T ) ; (D) c o m p l e x m u l t i g e n e r a t i o n a l A N T m i c r o b r e c c i a s ; (E) m i x e d (basaltic + A N T ) m i c r o b r e c c i a s ; (F) u l t r a m a f i e p a r t i c l e s (olivinea n d / o r p y r o x e n e - r i c h ) . P o p u l a t i o n s t u d i e s ind i c a t e t h e r e g o l i t h a t t h e Apollo 14 site is c h a r a c t e r i z e d b y a h i g h e r r a t i o of f r a g m e n t a l

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AFCRL B I B L I O G R A P I I Y - - 3 R D QUAI~TER 1 9 7 2

( d e g r a d e d ) t o p r i m a r y igneous lithie particles and a much higher ANT/basalt ratio than Apollo l l , 12, 15 a n d L u n a 16 soil samples. D e t a i l e d s t u d i e s of g r o u p s A, C, D, a n d F p e r m i t s e v e r a l p e t r o g e n e t i c conclusions: (1) A few Apollo 14 b a s a l t s r e s e m b l e m a r e b a s a l t s a n d p r o b a b l y h a v e similar origins as t h i n l a v a flows (from O c e a n u s P r o c e l l a r u m ) . (2) Most Apollo 14 b a s a l t i c p a r t i c l e s show affinities to K R E E P b a s a l t s a n d are p r e s u m e d to h a v e a n o n m a r e origin. (3) R a r e b a s a l t s w i t h t h e m o s t p r i m i t i v e M g / F e r a t i o s y e t r e p o r t e d for l u n a r m a t e r i a l s may represent ancient crustal material and/or melt compositions from the lunar interior from w h i c h m a n y l u n a r m a t e r i a l s were d e r i v e d ( i n c l u d i n g A N T ) . (4) A N T m a t e r i a l s were p r o d u c e d b y c u m u l a t e igneous d i f f e r e n t i a t i o n processes in e a r l y l u n a r h i s t o r y a n d were probably complemented by settled ultramafie c u m u l a t e s . (5) R a r e p r i m a r y igneous m a t e r i a l of l a t e - s t a g e d i f f e r e n t i a t e d c h a r a c t e r r e s e m b l e s u p p e r layers of t e r r e s t r i a l l a y e r e d g a b b r o i c c o m p l e x e s ; l i q u i d i m m i s c i b i l i t y a p p e a r s to be a n i m p o r t a n t m e c h a n i s m in l a t e - s t a g e l u n a r d i f f e r e n t i a t i o n . (6) A N T a n d u l t r a m a f l c m a t e r i a l s w e r e e x c a v a t e d f r o m d e p t h in t h e l u n a r c r u s t b y a m a j o r e r a t e r i n g e v e n t ( I m b r i u m ) . (7) R e s i d e n c e in a t h i c k h o t e j e c t a b l a n k e t ( F r a M a u r o f o r m a t i o n ) c a u s e d a n n e a l i n g a n d rec r y s t a l l i z a t i o n of f r a g m e n t a l t e x t u r e s . PttOVOST, A., AND BOTTINGA, Y., 1972. R a t e s of solidification of Apollo 11 b a s a l t a n d H a w a i i a n tholeiite. E a r t h Planet. Sei. Left. 15, 325 337. Cooling histories of Apollo I 1 b a s a l t flows h a v e been evaluated numerically. The temperature d e p e n d e n c e of t h e t h e r m a l diffusivity, t h e l i b e r a t i o n of t h e l a t e n t h e a t of fusion a t t h e site of crystallization, and radiation at the upper surface of t h e flows, h a v e b e e n i n c o r p o r a t e d in t h e calculations. I t is c o n c l u d e d t h a t in general t h e Apollo 11 b a s a l t s are s a m p l e s f r o m less t h a n 7 0 c m d e p t h in a flow, a n d t h a t t h e s a m p l e 10020 c o m e s f r o m a d e p t h less t h a n 10cm. To c h e c k t h e c o m p u t a t i o n s , t h e cooling of a H a w a i i a n t h o l e i i t i e l a v a lake was c a l c u l a t e d ; t h e r e s u l t s are in good a g r e e m e n t w i t h t h e o b s e r v e d d a t a o n t h e cooling of t h e K i l a u e a I k i a n d A l e a l a v a lakes. PUGH, M. J., 1972. R o t a t i o n of l u n a r d u m b b e l l s h a p e d globules d u r i n g f o r m a t i o n . N a t u r e 237, 158 159. T h e a u t h o r h a s p e r f o r m e d m e a s u r e m e n t s on some globules w h i c h s u p p o r t t h e s u g g e s t i o n t h a t t h e e j e c t a are m a s s e s of m e l t which assume a regular elongated shape governed b y t h e e q u i l i b r i u m b e t w e e n t h e o p p o s i n g effects o f surface t e n s i o n a n d r o t a t i o n of t h e globule. PUOH, M. J., AND BASTI~r, J . A., 1972. I n f r a r e d o b s e r v a t i o n s of t h e M o o n a n d t h e i r inter-

p r e t a t i o n . The M o o n 5, 16-30. T h e l u n a r spectrum, resulting from both the directly s c a t t e r e d solar r a d i a t i o n a n d t h e M o o n ' s i n t r i n s i c t h e r m a l r a d i a t i o n , is described. T h e v a r i a t i o n s of t h e t h e r m a l c o m p o n e n t w i t h l a t i t u d e a n d phase, a n d d u r i n g eclipse c o n d i t i o n s , are d e s c r i b e d a n d c o m p a r e d w i t h a p l a n e h o m o g e n e o u s m o d e l of t e m p e r a t u r e - i n d e p e n d e n t t h e r m a l c o n s t a n t s . A r e v i e w is g i v e n of t h a t d a t a a p p r o p r i a t e t o t h e l u n a r c r u s t w h i c h m a y be o b t a i n e d , b o t h f r o m c o m p a r i s o n of t h i s m o d e l with observation and from those modifications of t h e model, w h i c h e x p l a i n o t h e r w i s e a n o m a l o u s m e a s u r e m e n t s . F i n a l l y , a discussion of t h e v a r i o u s m e t h o d s of d e t e r m i n i n g t h e v e r t i c a l t e m p e r a t u r e g r a d i e n t a t t h e surface leads to a m e a n v a l u e of a b o u t 2 ° K i n -1, a l t h o u g h t h e h e a t flux associated w i t h t h e s e r e s u l t s is m u c h less than the recent direct measurement. QCAIDE, W., AND WRIGLEY, R., 1972. M i n e r a l o g y a n d origin of F r a M a u r o fines a n d breccias. Geochim. Cosmochim. A c t a S u p p l . 3, 1, 771-784. T e x t u r a l features, glassy s p h e r u l e a n d glassy a g g r e g a t e c o n t e n t s , a n d size-freq u e n c y d i s t r i b u t i o n s of lithic c o m p o n e n t s of t h e r e g o l i t h fines i n d i c a t e t h a t t h e F r a M a u r o r e g o l i t h of t h e s m o o t h t e r r a i n is a h i g h l y rew o r k e d a c c u m u l a t i o n of d e b r i s d e r i v e d p r i m a r i l y b y i m p a c t c o m m i n u t i o n of a n n e a l e d breecias. A n a l y s e s of t h e glassy s p h e r u l e s suggest t h a t m a r e - d e r i v e d d e b r i s m u s t a m o u n t to less t h a n 5 % of t h e regolith, b u t exotic m a t e r i a l s h a v i n g t h e c o m p o s i t i o n of t h e F r a M a u r o breccias (highland-like) c a n n o t b e recognized. B r e c c i a s a m p l e s f r o m t h e F r a M a u r o site i n c l u d e (1) r e g o l i t h breccias d e r i v e d b y lithification of local r e g o l i t h m a t e r i a l , (2) t e x t u r a l l y a n d comp o s i t i o n a l l y u n i q u e w h i t e r o c k breccias t h a t may have been derived from ancient ejecta buried beneath the Fra Mauro formation, and (3) a n n e a l e d breccias t h a t are e x c a v a t e d s a m p l e s of t h e F r a M a u r o f o r m a t i o n . T h e l a t t e r were d e p o s i t e d as h e a t e d i m p a c t ejecta, p r o b a b l y b y avalanches produced by the Imbrian event and were a n n e a l e d i n situ in a t h e r m a l r e g i m e p e r h a p s e q u i v a l e n t to t h a t r e s p o n s i b l e for t h e p y r o x e n e - h o r n f e l s facies of m e t a m o r p h i s m in t e r r e s t r i a l rocks. D i f f e r e n t degrees of a n n e a l i n g in different s a m p l e s reflect t h e i r original posit i o n s in t h e cooling deposit. L i t h i c f r a g m e n t s i n t h e a n n e a l e d breccias r e v e a l t h a t t h e source a r e a c o n s i s t e d of a p l u t o n i e c o m p l e x of feldsp a t h i c a n d u l t r a m a f i c rocks d o m i n a t e d b y noritic types that had been highly cratered to yield a t h i c k , c o m p l e x r e g o l i t h c o n t a i n i n g layers of r e w o r k e d d e b r i s of t h e r m a l l y a n n e a l e d e j e c t a a n d c o n t a i n i n g i n t e r c a l a t e d or c a p p i n g flows of b a s a l t of v a r i e d c o m p o s i t i o n .

M O O N - - S U R F A C E LAYER

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REID, A. M., WARNER, J., RIDLEY, W. I., AND contributing to the various soils. N o n m a r e rock BROWN, R. W., 1972. Major element composition t y p e s are characterized by high weight percent of glasses in three Apollo 15 soils. Meteoritics 7, AlzO 3 (>14), low F e O (<14), low Cr203 (<0.2) 395-415. A p p r o x i m a t e l y 180 glasses in each of and low CaO/A1203 (<0.7). Two m a j o r n o n m a r e three Apollo 15 soils h a v e been analyzed for nine rock types are recognized. F r a Mauro basalts elements. Cluster analysis techniques allow the ( K R E E P ) p r e d o m i n a t e at t h e Apollo 14 site, recognition of preferred glass compositions t h a t are a b u n d a n t in some Apollo 12 soils, b u t are are e q u a t e d w i t h p a r e n t rock compositions. u n c o m m o n in t h e Apollo 11 and L u n a 16 soils. Green glass rich in Fe and Mg, poor in A1 and Ti H i g h l a n d basalt, or anorthositic gabbro, is m a y be derived from deep seated pyroxenitic a b u n d a n t at all four sites and is i n t e r p r e t e d as m a t e r i a l now present at the A p e n n i n e F r o n t . a m a j o r rock t y p e in the lunar highlands. Apollo F r a Mauro basalt ( K R E E P ) is m o s t a b u n d a n t 11 and 12 basalts are higher in Fe, Cr and Ca/A1, in t h e LM soil and is t e n t a t i v e l y identified as r a y and lower in A1 t h a n t h e L u n a 16 basalts. m a t e r i a l f r o m t h e Aristillus-Autolycus area. I l m e n i t e pyroxenites form a m i n o r group at H i g h l a n d basalt (anorthositic gabbro), believed each m a r e site. Mare basalts p r o b a b l y are to be derived from t h e l u n a r highlands, has the partial melts of a pyroxenitic m a n t l e whereas same composition as at other landing sites, b u t H i g h l a n d basalts and possibly F r a Mauro is less a b u n d a n t . The A p e n n i n e F r o n t is p r o b a b l y basalts originate from a shallower, m o r e not t r u e highland m a t e r i a l b u t m a y contain a aluminous source region. The outer regions of substantial a m o u n t of material w i t h the comthe m o o n a p p a r e n t l y are heterogeneous and position of F r a Mauro basalt, b u t lacking the layered, w i t h a Ca-, Al-rich feldspathic crust h i g h - K content. Glasses w i t h m a r e basalt overlying a m o r e marie pyroxenitic m a n t l e a t compositions are present in the soils and four depth. REISZ, A. C., PAUL, D. L., AND MADDEN, T. R., subgroups are recognized, one of which is compositionally e q u i v a l e n t to t h e large Apollo 1972. L u n a r electrical c o n d u c t i v i t y . N a t u r e 15 basalt samples. 238, 144-145. Sonett et al. h a v e i n v e r t e d s u n w a r d REID, A. M., RIDLEY, W. I., HARMON, R. S., l u n a r surface m a g n e t o m e t e r d a t a to o b t a i n a WA~NER, J., BRETT, R., JAKE~, P., AND BROWN, lunar electrical c o n d u c t i v i t y profile, using t h e R. W., 1972. H i g h l y aluminous glasses in l u n a r poloidal m a g n e t i c response to a spatially soils and t h e n a t u r e of the l u n a r highlands. uniform source field of a radially s t r u c t u r e d Geochim. Cosmochim. A c t a 36,903-912. Approxiconducting sphere i m m e r s e d in an infinitely m a t e l y 25% of the glasses in two Apollo 14 soil conducting plasma. H o w e v e r , the spatial symsamples and in the soils at two levels in t h e m e t r y imposed on the b o u n d a r y conditions b y L u n a 16 core h a v e compositions e q u i v a l e n t to this model of t h e i n t e r p l a n e t a r y magnetic fieldanorthositic gabbro. Reassessment of the nonMoon interaction neglects t h e solar w i n d m a r e glass c o m p o n e n t s in t h e Apollo 11 and 12 p l a s m a - M o o n - v o i d g e o m e t r y and the finite soils shows t h a t glasses w i t h t h e composition of application t i m e of the i n t e r p l a n e t a r y m a g n e t i c anorthositie gabbro are c o m m o n to b o t h ; field which result from t h e solar wind flow p a s t gabbroic anorthosite glasses are less c o m m o n , t h e Moon. F r o m analysis of these effects, t h e and anorthositie glasses, rare. Anorthositic authors conclude t h a t the e x p e r i m e n t a l s u n w a r d gabbro glasses h a v e the same m a j o r element t a n g e n t i a l m a g n e t i c response does n o t exclude composition at all four sites, and resemble t h e a more c o n d u c t i v e l u n a r interior. I n a reply, S u r v e y o r 7 analysis from a " h i g h l a n d " site. Sonett et al. argue t h a t field line diffusion Thus, strong p r e s u m p t i v e evidence exists t h a t t h r o u g h the crust and p a s t t h e core can a c c o u n t m a t e r i a l w i t h this specific composition is for the v e r y large difference in transfer function. a b u n d a n t in the lunar highlands. RIDLEY, W. X., BRETT, R., WILLIAMS, R. J., REID, A. M., WA--~NER, J., RIDLEY, W. I., TAKEDA, n . , AND BRO~,VN,R. W., 1972. P e t r o l o g y JOHNSTON, D. A., HARMON, n . S., JAKES, P., of F r a Mauro basalt 14310. Geochim. Cosmochim. AND BROWN, R. W., 1972. The m a j o r element A c t a S u p p l . 3, 1, 159-170. A petrological s t u d y compositions of lunar rocks as inferred from of rock 14310 indicates t h a t it contains a b o u t 10% plagioclase phenocrysts and m a y n o t glass compositions in the lunar soils. Geochim. Cosmochim. A c t a S u p p l . 3, 1, 363-378. D a t a on necessarily represent a t o t a l m e l t composition. t h e m a j o r e l e m e n t composition of glasses in The plagioclase compositions can be e x p l a i n e d Apollo 11, 12 and 14 and L u n a 16 soils h a v e been b y rapid crystallization in a closed s y s t e m classified into groupings of preferred comw i t h o u t requiring N a volatilization. Plagioclaso positions b y cluster analysis techniques. These crystallization was followed b y o r t h o p y r o x e n e , preferred compositions are i n t e r p r e t e d as being pigeonite, a n d augite, and ilmenite, c h r o m i a n r e p r e s e n t a t i v e of the composition of rock t y p e s ulv6spinel, and metal, leaving a siliceous,

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AFCRL B I B L I O G R A P H ¥ - - 3 R D QUARTER 1 9 7 2

p o t a s s i u m - r i c h mesostasis. U n l i k e m a r e p y r o x enes, m e t a s t a b l e p y r o x e n e s a n d a u g i t e p y r o x e n e are rare. T h e f%, a t least d u r i n g t h e early p o r t i o n of c r y s t a l l i z a t i o n , was h i g h e r t h a n t h a t p e r t a i n i n g d u r i n g t h e e a r l y c r y s t a l l i z a t i o n of Apollo 12 basalts. T h e h i g h e r solidus a n d l i q u i d u s t e m p e r a t u r e s of 14310 c o m p a r e d to m a r e basalts, b u t g r e a t e r e n r i c h m e n t in c e r t a i n l i t h o p h i l e t r a c e e l e m e n t s are i n c o n s i s t e n t w i t h 14310 a n d m a r e b a s M t s b e i n g d i r e c t l y g e n e t i c a l l y related, a n d suggest c h e m i c a l l y different source areas. ROEDDER, E., AND WEIBLEN, P. W., 1972. O c c u r r e n c e of e h r o m i a n , h e r c y n i t i c spinel ( " p l e o n a s t e " ) in Apollo-14 s a m p l e s a n d its petrologic i m p l i c a t i o n s . E a r t h Planet. Sci. Lett. 15, 376-402. M a n y isolated g r a i n s of a r e d d i s h p l e o n a s t e - t y p e spinel occur in fines a n d r e c t a breccia samples, p a r t i c u l a r l y 14319. E l e c t r o n m i c r o p r o b e a n a l y s e s (104) of spinels a n d t h e i r a s s o c i a t e d p h a s e s include 58 of p l e o n a s t e w h i c h show Mg/(Mg + Fe) 0.44 + 0.62 a n d Cr/(Cr + A1) 0.017-0.134 (atomic), plus m i n o r a m o u n t s of o t h e r ions, a n d differ g r e a t l y f r o m a l m o s t all p r e v i o u s l y r e c o r d e d l u n a r spinels; a l m o s t no spinels of i n t e r m e d i a t e c o m p o s i t i o n were f o u n d . T w o t y p e s of c o m p o s i t i o n a l z o n i n g exist • a diffuse p r i m a r y one w i t h cores lower in Ti, a n d a n a r r o w s e c o n d a r y one f r o m r e a c t i o n w i t y m a t r i x yielding r i m s h i g h e r in Cr, Ti, a n d Mn. A t c o n t a c t s w i t h b r e c c i a m a t r i x t h e r e is a n a r r o w c o r o n a of a l m o s t p u r e plagioelase (An8o An94), free of o p a q u e m i n e r a l s a n d p y r o x e n e . Two t y p e s of solid inclusions f o u n d in t h e p l e o n a s t e are ealeie plagioelase, a n d t i n y s p h e r i c a l m a s s e s of nickelrich sulfide. Similar p l e o n a s t e occurs in c r y s t a l l i n e r o c k clasts, m a i n l y w i t h plagioelase; one elast (A) consists o n l y of coarse olivine, plagioclase, and pleonaste, with granulated grain boundaries s u g g e s t i v e of d e f o r m a t i o n . F r o m c o m p o s i t i o n a n d t e x t u r e , t h i s elast is one possible c a n d i d a t e for t h e marie c u m u l a t e c o u n t e r p a r t of t h e " a n o r t h o s i t i e " crust. A n o t h e r clast (B), also m a d e solely of olivine, plagioclase a n d pleonaste, is itself a breccia. T h e s e d a t a suggest a t w o - s t a g e b r e c c i a t i o n process: (1) d i s r u p t i o n ( p r o b a b l y p r e - I m b r i a n ) of a d e e p . s e a t e d p l e o n a s t e - b e a r i n g source r o c k like A a n d r e e o n s o l i d a t i o n to f o r m a b r e c c i a w i t h o u t a d d i t i o n of p y r o x e n e , i l m e n i t e or o t h e r m i n e r a l s ; a n d (2) d i s r u p t i o n o f t h i s b r e c c i a to yield breccia elast B w h i c h was t h e n i n c o r p o r a t e d into t h e F r a M a u r o f o r m a t i o n . ROEDDER, E., AND WEIBLEN, t ). W., 1972. P e t r o g r a p h i c f e a t u r e s a n d petrologic significance of m e l t inclusions in Apollo 14 a n d 15 rocks. Geochim. Cosrnochim. Acta S u p p l . 3, 1, 251-279. T h e o c c u r r e n c e a n d significance o f silicate m e l t inclusions in a series of Apollo 14 a n d 15 igneous rocks, breccias, a n d soils are described. E l e c t r o n

m i c r o p r o b e a n a l y s e s (114) are r e p o r t e d , g i v i n g t h e b u l k c o m p o s i t i o n of r e p r e s e n t a t i v e inclusions as well as t h e i r d a u g h t e r a n d h o s t m i n e r a l s a n d o t h e r p h a s e s associated w i t h t h e inclusions. A l t h o u g h m a n y of t h e f e a t u r e s seen are similar t o t h o s e p r e v i o u s l y described, some n o v e l ones were f o u n d . Silicate m e l t inclusions in olivine are a b u n d a n t a n d occasionally large (400/zm). N u c l e a t i o n a n d g r o w t h (epitaxial or r a n d o m ) of d a u g h t e r p h a s e s varies w i t h inclusion size, b u l k c o m p o s i t i o n , a n d p r o b a b l y w i t h cooling h i s t o r y . Solid inclusions in olivine consist of r e l a t i v e l y large Cr-spinel e u h e d r a (20-40/~m) ; t h e olivines in t h e r m a l l y m e t a m o r p h o s e d rocks h a v e , in a d d i t i o n , rows of v e r y m i n u t e Cr-rich c r y s t a l s (~lt,nl) that have decorated what apparently are o t h e r w i s e invisible dislocations. T i n y m e l t inclusions in f r a c t u r e s in plagioelase of 15415 i n d i c a t e t h e p r e s e n c e of a t least a s m a l l a m o u n t of m e l t a t t h e t i m e of f r a c t u r i n g . Melt inclusions r e l a t e d to t h e o n s e t of i m m i s c i b i l i t y are c o m m o n in all t h e samples, p a r t i c u l a r l y 14310, a n d are like t h o s e in Apollo 11 a n d 12 a n d L u n a 16 samples--potassie granite and ferropyroxenite in c o m p o s i t i o n . T h e r e is a n i n v e r s e r e l a t i o n s h i p b e t w e e n t h e K 2 0 / N a 2 0 r a t i o in t h e b u l k r o c k a n d its residual high-silica m e l t . A s u m m a r y of all t h e a u t h o r s ' m e l t inclusion d a t a in t h e f o r m of a single silica v a r i a t i o n d i a g r a m suggests grossly similar liquid lines o f d e s c e n t for t h e v a r i o u s igneous rock t y p e s s a m p l e d a t t h e five l a n d i n g sites. All t h e s e lines a p p e a r to e n d a t t h e s a m e high-silica m e l t c o m p o s i t i o n . N u m e r o u s areas a n d f r a g m e n t s of glass of p o t a s s i e g r a n i t e c o m p o s i t i o n ( p a r t l y crystallized to a K - f e l d s p a r ) were f o u n d in t h e Apollo 14 breeeias. T h e r e s i d u a l glass in t h e s e f r a g m e n t s is v e r y s i m i l a r in c o m p o s i t i o n to t h a t of t h e high-silica immiscible m e l t a n d could r e p r e s e n t a p h a s e of g r a n i t i c c o m p o s i t i o n f r o m t h i s process t h a t occurs in t h e c r u s t of t h e m o o n a n d was c o n c e n t r a t e d in t h e Apollo 14 source m a t e r i a l s . SCHt~R~ANN, K., AND HAFNER, S, S., 1972. D i s t i n c t subsolidus cooling histories of Apollo 14 basMts. Geochim. Cosmochim. A c t a S u p p l . 3, l, 493 506. T h e Mg 2+, F e 2+ e x c h a n g e r e a c t i o n b e t w e e n t h e M1 a n d M2 sites is a n a l y z e d in n a t u r a l a n d h e a t e d s a m p l e s of p i g e o n i t e f r o m b a s a l t 14053,47 a n d o r t h o p y r o x e n e f r o m b a s a l t 14310,116. T h e d i s t r i b u t i o n coefficient k~ in o r t h o p y r o x e n e 14310 is smaller t h a n t h e critical coefficient /c~. I t c o r r e s p o n d s to a n e q u i l i b r i u m t e m p e r a t u r e of a p p r o x i m a t e l y 600°C. T h e subsolidus cooling of b a s a l t 14310 o c c u r r e d a t t h e d e p t h o f several m e t e r s in a c o h e r e n t b o d y of a p p r e c i a b l e size. It, of p i g e o n i t e 14053 is significantly g r e a t e r t h a n ]cc. I t c o r r e s p o n d s to a n equilibrium temperature of a p p r o x i m a t e l y

MOON--SURFACE LAYER

840°C. 14053 must have been quenched extremely rapidly from a temperature higher than Tn probably by impact at Fra Mauro as a fragment of a larger body from the Imbrian ejecta. SCHORMANN, K., AND HAFNER, S. S., 1972. On the amount of ferric iron in plagioclases from lunar igneous rocks. Geochim. Cosmochim. Acta Suppl. 3, 1, 615-621. M6ssbauer spectra of S~Fe in plagioclases from rocks 14053, 14310, and 15415 and from terrestrial anorthosites and basalts have been studied. The center of gravity of the total resonance absorption area has been tentatively interpreted in terms of the Fe3+/Fetot ratio. The significantly different values can be correlated with oxygen partial pressure conditions during crystallization. SCLAR, C. B., AND MORZENTI, S. P., 1972. Electron microscopy of some experimentally shocked counterparts of lunar minerals. Geochim. Cosmochim. Acta Suppl. 3, 1, 1121-1132. Particulate samples of experimentally shocked olivine, enstatite, and apatite and their unshocked equivalents were thinned by ion bombardment and examined by transmission methods in a conventional (100kV) electron microscope. Enstatite shock-loaded at a peak pressure of 250kb was partly transformed to relatively dense inverse defect spinel. Magnesian olivine shocked at a peak pressure of 200kb shows intense lattice deformation. Magnesian olivine shock-loaded at a peak pressure of 400 kb was recrystallized to very fine polycrystalline aggregates. Apatite shock-loaded at a peak pressure of 250kb shows planar deformation elements and shock-induced imperfections. These results indicate that this experimental approach has considerable potential as a means of developing shock-recognition criteria for minerals of lunar rocks. SKINNER, B. J., AND WINCHELL, H . , 1972. Mineralogical evidence for subsolidus vaporphase transport of alkalis in lunar basalts. Geochim. Cosmochim. Acta Suppl. 3, 1, 243-249. Thin, potassium-rich margins to feldspar grains, and along cracks within feldspar grains, in lunar basalts 12038 and 12040 provide evidence of late-stage and presumably subsolidus movement of material in the vapor phase. The compositions of the vapors are not known but are inferred to be alkali-rich relative to the parent rock. The same vapors are postulated to deposit perfect, whisker crystals of alkali-rich plagioclase in vugs and vesicles of 12038. SMITH, D. K . , THROWER, P. A., AND HOFFMAN, W. P., 1972. Electron petrography of Apollo sample 14310. Geochim. Cosmochim. ActaSuppl. 3, 1,231-241. Thin sections prepared from Apollo sample 14310 have been examined

105

with 100kV transmission electron microscopy. The sample is composed principally of anorthite and pyroxene. The anorthites fall into two categories. The transitional anorthites t h a t show the characteristic "c" type diffraction maxima are characterized by very fine antiphase domain structures and some fine twinning. The bodycentered anorthites that show no "c" reflections are characterized by an absence of fine twinning and a less well-defined antiphase domain structure. Although both orthopyroxene and clinopyroxenes are reported in sample 14310, only clinopyroxenes were observed in this study and all show exsolution structures. The augite exsolved in pigeonite commonly is along lamefiae parallel to (100), although (001) lamellae also are present. This unusual orientation (001) lamellae commonly are most prominent) was verified by diffraction patterns. The pigeonite commonly shows antiphase domains, attributed to stacking errors when the sample inverted from its high temperature disordered form. In augite as the host phase, the pigeonite lamellae contain very complex structures including antiphase domains. STEELE, I. M., AND SMIT~, J. V., 1972. Compositions and mineralogy of lithic fragments in 1-2ram soil samples 14002,7 and 14258,33. Geochim. Cosmochim. Acta Suppl. 3, 1, 971-981. Broad-beam electron microprobe analyses of igneous-textured fragments from 1-2ram fines 14002,7 and 14258,33 as well as from larger rock sections 14310,175 and 14072,10 suggest three principal igneous rock types at the F r a Mauro site. The first (I) is a plagioclase-rich basalt characterized by high CaO and A1203; the second (II) is a picrobasalt characterized by high MgO relative to FeO resulting from abundant high-Mg, low-Ca pyroxene and minor olivine; the third rock Type (III) is an Fe-rich basalt with coarse texture similar to some Apollo 12 mare-type basalts. The bulk composition of the plagioclase-rich rock type closely matches the analysis of Tyeho material obtained by Surveyor VII. Averaged Apollo 14 soils analyses are well represented by 39% I + 35% I I ÷ 26% I I I . Glass compositions from 14259 soil (Apollo Soil Survey) do not match these three groups of analyses, suggesting a different origin. Types I and I I belong to the K R E E P group and differ mainly in proportions of plagioclase and Ca-poor pyroxene. They could be related to crystal-liquid fractionation involving these two minerals. An olivine-chromite fragment has an olivine with a composition (88-89mole% F o ; CaO 0.05wt%) consistent with early differentiation under plutonic conditions.

106

AFCRL B I B L I O G R A P I t ¥ - - 3 R D QUARTEI~ 1 9 7 2

STEELE, I. M., AND SI~IITIt, J . V., 1972. O c c u r r e n c e of diopside a n d C r - Z r - A r m a l c o l i t e o n t h e Moon. Nature 2 3 7 , 1 0 5 - 1 0 6 . T h e r e l a t i v e l y p u r e diopside a n a l y s e s r e p o r t e d h e r e r e p r e s e n t t h e m o s t Mg-rich calcic p y r o x e n e r e p o r t e d f r o m lunar material. This composition, together with t h o s e of t h e o t h e r p r i n c i p a l phases, i n d i c a t e s t h a t t h e low F e / M g r a t i o of t h i s f r a g m e n t is consistent with a product resulting from early erystM-liquid differentiation. The high chromium c o n t e n t of t h e C r - Z r - a r m a l c o l i t e h a s b e e n i n t e r p r e t e d as a n i n d i c a t i o n of a h i g h f o r m a t i o n t e m p e r a t u r e ; t h i s is c o n s i s t e n t w i t h t h e h i g h t e m p e r a t u r e e x p e c t e d for t h e f e r r o m a g n c s i a n m i n e r a l s . I t is t e n t a t i v e l y p r o p o s e d t h a t t h e f r a g m e n t was e j e c t e d d u r i n g a deep i m p a c t ( p e r h a p s I m b r i a n ) f r o m a n u l t r a m a f i c region a t d e p t h i n t h e Moon. TAJ~:EDA, H . , AND I~IDLEY, W. I., 1972. C r y s t a l l o g r a p h y a n d c h e m i c a l t r e n d s of o r t h o p y r o x e n e - p i g e o n i t e f r o m r o c k 14310 a n d coarse fine 12033. Geochim. Cosmochim. Acta Suppl. 3, 1, 423-430. X r a y single c r y s t a l d i f f r a c t i o n studies, s u p p l e m e n t e d b y e l e c t r o n m i c r o p r o b e a n a l y s e s of o r t h o p y r o x e n e s a n d p i g e o n i t e s f r o m r o c k chip 14310,90, h a v e identified t h e following Fra Mauro pyroxenes: bronzite with minor e x s o l u t i o n of a u g i t e o n (100) ; t w i n n e d m a g n e s i a n p i g e o n i t e w i t h m i n o r e x s o l u t i o n of a u g i t c o n (100) a n d (001), w i t h or w i t h o u t core b r o n z i t e s h a r i n g (100); m o r e F e - r i c h pigeonite, a n d a u g i t e t h a t r e s e m b l e s some eucritic p y r o x e n e s . T h e c a t i o n d i s t r i b u t i o n coefficient, (Fe/Mg)M1/ (Fe/Mg)M 2, of a 14310 b r o n z i t e refined b y X r a y m e t h o d s is 0.10, w h i c h is similar to t h a t of a b r o n z i t e of t e r r e s t r i a l v o l c a n i c origin. T h e f e a t u r e s of o v e r g r o w t h a n d exsolution, w h i c h are d i s t i n c t f r o m t h o s e of m a r e p y r o x e n e s , i n d i c a t e t h a t c r y s t a l l i z a t i o n w a s n o t as rectas t a b l e as t h a t of m a n y m a r c rocks b u t was m u c h m o r e r a p i d t h a n t h a t of p l u t o n i e or i n t r u s i v e rocks. T A N A ~ , S., SAKAMOTO, K., AND KOMURA, K., 1972. A l u m i n u m 26 a n d m a n g a n e s e 53 p r o d u c e d b y solar-flare particles in l u n a r r o c k a n d cosmic d u s t . J. Geophys. Res. 77, 4281-4288. W i t h t h e use of t h e e x c i t a t i o n f u n c t i o n s for 26Al-producing r e a c t i o n s m e a s u r e d b y t h e a u t h o r s , t h e r a t e s of 26A1 p r o d u c t i o n in i n t e r p l a n e t a r y t a r g e t s ( l u n a r rocks 10017 a n d 12002 a n d cosmic d u s t ) b y solar-flare particles h a v e b e e n c a l c u l a t e d . T h e s a m e c a l c u l a t i o n s h a v e also b e e n m a d e for 53Mn with the estimated excitation functions. The e n e r g y s p e c t r u m o f solar p r o t o n s a v e r a g e d o v e r t h e 1956-1966 solar cycle was u s e d as a g u i d e for t h e u n k n o w n flux o v e r t h e l a s t few million y e a r s w i t h t h e a s s u m p t i o n t h a t t h e r a t i o of I-I/He was 6. I t is s h o w n t h a t t h e h a l f - v a l u e of

t h e a v e r a g e flux r e p r o d u c e s r a t h e r well tile o b s e r v e d d e p t h profiles of t h e s e n u c l i d e s in t h e l u n a r rocks a n d t h e o b s e r v e d l i m i t of 26Al in m a r i n e s e d i m e n t . A slight d i s c r e p a n c y b e t w e e n t h e c a l c u l a t e d a n d t h e o b s e r v e d p a t t e r n of 53Mn a t t h e t o p surface of l u n a r rocks is discussed in t e r m s of surface erosion a n d o t h e r effects. T h e p r e s e n t c a l c u l a t i o n s are c o m p a r e d w i t h earlier ones. TAYLOR, G. J . , MARVIN, V. S., REID, J . B., JR., AND WOOD, J , A., 1972. N o r i t i c f r a g m e n t s in t h e Apollo 14 a n d 12 soils a n d t h e origin of O c e a n u s P r o c e l l a r u m . Geochim. Cosmochim. A cta Suppl. 3, 1, 995-1014. F r a g m e n t s of n o r i t i c breccias h a v i n g a r a n g e of r e c r y s t a l l i z a t i o n t e x t u r e s a n d n o r i t i c b a s a l t s c o m p r i s e a b o u t 8 0 % of t h e 1 - 2 m m soil s a m p l e s f r o m Cone C r a t e r (14142) a n d t h e b o t t o m of t h e t r e n c h (14151). I n five o t h e r samples, n o r i t i c f r a g m e n t s r a n g e in a b u n d a n c e f r o m 4 2 - 5 6 % . T h e r e m a i n i n g particles in each ease are glasses, soil breccias, a n d g l a s s - b o n d e d a g g r e g a t e s ; o t h e r c r y s t a l l i n e rock t y p e s such as a n o r t h o s i t c s c o n s t i t u t e less t h a n 1 % of t h e soil. Noritie m a t e r i a l s , i.e., Apollo 12 a n d 14 n o r i t e s a n d r o p y ( K R E E P ) glass particles, c a n b e d i v i d e d i n t o t w o b r o a d g r o u p s on a c h e m i c a l basis. T h e p a r t i c l e s in one g r o u p h a v e r e l a t i v e l y h i g h b u l k TiO 2 c o n t e n t s a n d h i g h F c / ( F e + M g ) r a t i o s in t h e i r n o r m a t i v e p y r o x e n e s ; t h e r o p y glasses f r o m Apollo 12 a n d 14 a n d a few Apollo 12 n o r i t i c rock fragm e n t s are in t h i s category. P a r t i c l e s in t h e o t h e r class c o n t a i n p y r o x e n e s w i t h a lower F e / ( F e + Mg) a n d h a v e a r a n g e of TiO2 c o n t e n t s ; m o s t n o r i t i c rock f r a g m e n t s f r o m Apollo 12 a n d 14 are in t h i s group. T h e r o p y glasses m a y b e f r o m Copernicus or o t h e r r a y e d craters, b u t a l m o s t all t h e n o r i t e s d e r i v e f r o m t h e F r a u M a u r o f o r m a t i o n or o t h e r noritic o c c u r r e n c e s a s s o c i a t e d w i t h O c e a n u s P r o c e l l a r u m . N o n - K R E E P comp o n e n t s in t h e Apollo 14 soil include glasses h a v i n g t h e c o m p o s i t i o n s of a n o r t h o s i t i c g a b b r o , mare basalts, and howarditic meteorites; but t h e r e are n o c r y s t a l l i n e e q u i v a l e n t s of t h e s e glasses in o u r soil samples. A p p a r e n t l y , c r a t e r i n g p r o j e c t s glassy d e b r i s g r e a t e r d i s t a n c e s o n t h e m o o n t h a n it does lithic f r a g m e n t s . L u n a r n o r i t e a p p e a r s t o be a s s o c i a t e d u n i q u e l y w i t h O c e a n u s Procellarum, the largest uninterrupted mare surface on t h e m o o n . T h e a u t h o r s suggest t h a t t h e P r o c e l l a r u m B a s i n was e x c a v a t e d b y m u l t i p l e i m p a c t s of p l a n e t e s i m M s , focused o n t h e e a r t h - f a c i n g side of t h e m o o n b y t e r r e s t r i a l gravity; and that heat generated by this concerted bombardment promoted partial melting in or u n d e r t h e local a n o r t h o s i t i c crust, g i v i n g rise to n o r i t i c m a g m a s . TAYLOR, S. R., GORTON, M. P., MUIR, P.,

MOON--SURFACE

NANCE, W., RUDOWSKI, n . , AND WARE, N., 1972. T r a c e e l e m e n t g e o c h e m i s t r y of Apollo 16 soil 68501. N a t u r e 230, 205-207. A n a l y s i s of s a m p l e 68501,46 shows t h e following: Nickel ( 4 2 0 p p m ) is a f a c t o r of t w o g r e a t e r t h a n m o s t soils a n a l y s e d p r e v i o u s l y . Metallic f r a g m e n t s w i t h m e t e o r i t i c c o m p o s i t i o n s are also m o r e c o m m o n . I f t h e s a m p l e is r e p r e s e n t a t i v e of t h e Cayley F o r m a t i o n , t h e n t h i s i n c r e a s e d m e t e o r i t i c component may be indigenous (pre-South Ray Crater) a n d d e r i v e d f r o m t h e e a r l y ( p r e - I m b r i u m ) h i g h l a n d c r a t e r i n g . T h a t is n o t c o n s i s t e n t w i t h t h e geological i n t e r p r e t a t i o n of t h e Cayley F o r m a t i o n as a v o l c a n i c c o n s t r u c t i o n a l u n i t , b u t agrees w i t h t h e view t h a t it r e p r e s e n t s preImbrimn crust thoroughly mixed by cratering. T h e a l t e r n a t i v e e x p l a n a t i o n , t h a t t h e excess Ni comes f r o m t h e m e t e o r i t e w h i c h p r o d u c e d t h e S o u t h R a y Crater, c a n o n l y b e e v a l u a t e d b y a n a l y s e s of f u r t h e r soil s a m p l e s r e m o t e f r o m S o u t h R a y ejecta. T h e general s i m i l a r i t y b e t w e e n t h e e l e m e n t a l a b u n d a n c e s r e p o r t e d for this highland sample with those reported from s a m p l e s f r o m earlier missions is striking. TERA, F., AND WASSERBCRG, G. J., 1972. U - T h - P b s y s t e m a t i c s in t h r e e Apollo 14 b a s a l t s a n d t h e p r o b l e m of initial P b in l u n a r rocks. E a r t h and P l a n e t a r y Science Letters 14, 281-304. T h e isotopic c o m p o s i t i o n of P b a n d t h e e l e m e n t a l c o n c e n t r a t i o n of U, T h a n d P b were m e a s u r e d o n " t o t a l " r o c k s a m p l e s 14053, 14073 a n d 14310 a n d o n m i n e r a l s e p a r a t e s of 14310 a n d I4053. S a m p l e No. 73 a p p e a r s to b e q u i t e similar t o No. 310. S a m p l e No. 310 yields t o t a l rock m o d e l ages of T ( 2 ° 6 p b / z a s u ) = 4 . 2 4 A E , T(2°Tpb/zasU) 4 . 2 7 A E , a n d T(2°spb/aa2Th) = 4 . 1 3 A E . T h e s e are n e a r l y c o n c o r d a n t a n d d i s t i n c t f r o m t h e R b - S r a n d K - A r c r y s t a l l i z a t i o n ages of 3 . 8 8 A E . M i n e r a l s e p a r a t e s f r o m 14310 s h o w a wide s p r e a d in 2°vpb/2°6pb r a n g i n g f r o m 0.483 to 0.995. T h e d a t a p o i n t s define a r e a s o n a b l e l i n e a r a r r a y on t h e c o u p l e d P b - U e v o l u t i o n d i a g r a m . Similar a n a l y s e s of 14053 give h i g h , d i s c o r d a n t t o t a l rock m o d e l ages of T(2°apb/23su) = 5 . 6 0 A E , T(z°~pb/235U) = 5 . 1 8 A E , a n d T ( 2 ° s p b / ZaZTh) = 5 . 4 8 A E . M i n e r a l s e p a r a t e s show a r a n g e of z°zPb/2°6pb f r o m 0.716 t o 1.209. T h e s e d a t a also define a r e a s o n a b l e l i n e a r a r r a y on the coupled Pb-U evolution diagram. These are t h e first P b - U i s o c h r o n s o b t a i n e d for l u n a r basalts and indicate a reasonable solution to the p r e v i o u s d i s c r e p a n c y b e t w e e n t h e different m e t h o d s of " a b s o l u t e " age d e t e r m i n a t i o n . T h e r e s u l t i n g U - P b i s o c h r o n ages are c o m p a t i b l e w i t h t h e R b - S r a n d K - A t ages o n t h e s a m e rocks. H o w e v e r , it is n o t possible t o e s t a b l i s h a precise t i m e of " c r y s t a l l i z a t i o n " f r o m t h e P b - U d a t a b e c a u s e of t h e s m a l l a n g l e of i n t e r s e c t i o n b e t w e e n -

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t h e l i n e a r a r r a y s a n d t h e c o n c o r d i a curve. T h e s e d a t a show t h a t t o t a l r o c k m o d e l ages do n o t in g e n e r a l yield c r y s t a l l i z a t i o n ages. T h e d a t a o n No. 310 a n d No. 053 show t h a t t h e s e rocks were f o r m e d c o n t a i n i n g a h i g h l y radiogenic initial lead (2°~pb/2°6pb)lo ~ 1.46 w h i c h a c c o u n t s for t h e excessively h i g h t o t a l rock m o d e l ages b y t h e U - T h - P b m e t h o d . T h e o n l y significant d i s c r e p a n c y in t h e d a t a is t h e a p p a r e n t v a r i a b i l i t y of (2°spb/2°6pb)1o in No. 053 w h i c h r e m a i n s to b e resolved. T h e (2°Tpb/2°6pb)1o in t h e s e rocks c o r r e s p o n d s t o t h e r a d i o g e n i c lead e v o l v e d b e t w e e n 4.51 a n d 3 . 8 8 A E i n a U - r i c h e n v i r o n m e n t . S u c h d a t a f r o m initial P b m a y p r o v i d e a n e w c h r o n o m e t e r for e a r l y l u n a r e v o l u t i o n . T h e h i g h 2°7pb/2°6pb ages in some t o t a l l u n a r soils as well as in t r e a t e d f r a c t i o n s m a y be p a r t l y e x p l a i n e d as a c o n s e q u e n c e of t h e c o n t r i b u t i o n of l u n a r b a s a l t s w i t h r a d i o g e n i c initial P b . T h e d a t a p r o v e t h a t a t t h e t i m e of e x t r u s i o n of some b a s a l t s , u n s u p p o r t e d l e a d w i t h e x t r e m e l y h i g h 2°vpb/2°6pb r a t i o s was a d d e d to t h e l u n a r surface. TKIEL, K., HERtt, W., A~D BECKEI~, J., 1972. U r a n i u m d i s t r i b u t i o n in b a s a l t f r a g m e n t s of five l u n a r samples. E a r t h Planet. Sci. Lett. 16, 31-44. T h e U - d i s t r i b u t i o n in selected b a s a l t i c f r a g m e n t s f r o m l u n a r fines 10084, rocks 12021 a n d 12053 a n d brcccias 14305 a n d 1432I w a s s t u d i e d b y m e a n s of fission t r a c k s i n m i c a d e t e c t o r s . U - e n r i c h e d m i n e r a l p h a s e s were localized w i t h a n a c c u r a c y of b e t t e r t h a n 1/~m b y a p p l y i n g a photographic mapping technique. Identification a n d e l e m e n t a l a n a l y s i s were c a r r i e d o u t u s i n g a n e l e c t r o n m i c r o p r o b e . P h a s e s of h i g h U - c o n t e n t were identified as a p a t i t e ( 3 0 - 2 8 0 p p m ) , SiOzrich glasses ( 3 - 1 5 0 p p m ) or f i n e - g r a i n e d Zrc o n t a i n i n g m i n e r a l s of g r a i n sizes < l / ~ m (50450ppm). These U-enriched phases preferentially o c c u r i n t h e mesostasis. A n i n v e r s e r e l a t i o n s h i p was f o u n d b e t w e e n t h e U - c o n c e n t r a t i o n a n d t h e v o l u m e of t h e m e s o s t a s i s regions. T h e r a t i o of t h e U - c o n t e n t s of t h e r e s i d u a l l i q u i d a n d t h e m a j o r p h a s e s is c o m p a r a b l e w i t h t h a t f o u n d in terrestrial basalts. TRZCIENSKI, W . E., JR., AND KULICX, C. G., 1972. Plagioelase a n d B a - K p h a s e s f r o m Apollo s a m p l e s 12063 a n d 14310. Geochim. Cosmochim. A c t a S u p p l . 3, 1, 591-602. Plagioclases in Apollo 12 s a m p l e 12063 b e g a n g r o w t h as hollow c r y s t a l s c o m m o n l y enclosing a l a t e c r y s t a l l i z i n g pyroxene. With continued growth away from t h e i n i t i a l shell of t h e hollow plagioclase c r y s t a l , s e c t o r z o n i n g as well as n o r m a l z o n i n g (An9aAnso) p a t t e r n s d e v e l o p e d . R e l a t i v e e n r i c h m e n t in p o t a s s i u m (0.06 to 1.89% K 2 0 ) , iron (0.63 t o 1.12% FeO), a n d b a r i u m (0.00 t o 0 . 0 4 % B a O ) occurs t o w a r d t h e o u t e r g r a i n m a r g i n s . Also i n

108

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BIBLIOGRAPH¥--3RD QUARTER 1972

12063 late-stage mesostases containing two distinct K - B a phases exist; One phase contains 12.2% BaO and is a celsian-orthoclase feldspar whereas the other phase is a potassium-rich silica glass. In contrast, plagioclases from Apollo 14 sample 14310 are more anorthitic (An96-Anss) than those in 12063, and they occur in two distinct habits. The two morphologically different plagioclases m a y be related to liquid immiscibility. A late-stage potassium feldspar also occurs in sample 14310. The high potassium phases and liquid immiscibility suggest that " gr an i t e" may exist on an unsampled portion of the lunar surface. TSAr, F.-D., CHAN, S. I., AND MANATT, S. L., 1972. Electron paramagnetic resonance of radiation damage in a lunar rock. Nature 237, 121-122. Evidence is presented for the presence of radiation induced E P R signals in one of the lunar samples ( 12021-42). VINOO~ADOV, A., 1972. Lunar rock. EOS 53, 820-822. In February, a Soviet "automatic geologist" made a soft landing in a mountainous continental area of the moon and took samples of rocks. The author describes the results of the investigation of the rock delivered to the earth by the Luna 20 probe. VIRGO, D., AND I~AFNER, S. S., 1972. Temperature-dependent Mg, Fe distribution in a lunar olivine. Earth Planet. Sci. Lett. 14, 305-312. The nuclear hyperfine doublets of S7Fe at the two nonequivalent octahedrally coordinated positions M1 and M2 in an olivine Mgo.a4Feo.66SiO4 from lunar basalt 12018 have been analyzed in the temperature range between 250 and 450°C. The Mg 2+, Fe e+ is somewhat ordered, the Fe occupancy being greater at one of the two M positions by approximately 20%. After heating at 1155°C for seven days, the distribution was almost completely disordered. Studies of natural and heated olivines from terrestrial rocks show that the Mg 2+, Fe z+ exchange reaction in olivines is considerably more sluggish than in chain silicates. Generally no change in site occupancy can be observed after heating at temperatures of approximately 900°C over several days. The observed degree of ordering in the lunar olivine is indicative of slow cooling during crystallization. VON ENG]~LHAI~DT,W., ARNDT, J., STOFFLER, D., AND SCHNEIDER,H., 1972. Apollo 14 regolith and fragmental rocks, their compositions and origin by impacts. Geochim. Cosmochim. Acta Suppl. 3, l, 753-770. Fragmental rocks of Apollo 14 have been classified into three types according to their texture and modal composition: (1) glass-rich regolith breccias produced by impacts into the regolith ; (2) glass-poor breccias with fragmental matrices, forming the lower

member of the F r a Mauro formation, the ejecta blanket of the Imbrian event; (3) glass-poor fragmental rocks with crystalline matrices, forming the uppermost layer of the Fra Mauro ejecta blanket which is supposed to be the product of a hot base surge. The Apollo 14 regolith and the regolith breccias contain preImbrian material, derived from the F r a Mauro formation, and were mainly produced by local impacts. The admixture of mare basalts and highland material shows the influence of further distant impact events. Shock effects in minerals and rock fragments from the rcgolith and fragmental rocks include: fragmentation and undulatory extinction of all transparent minerals; deformation lamellae in pyroxene, olivine and ilmenite; isotropic lamellae, partial isotropization of plagioclasc and diaplectic plagioclase glass; shock fusion of rocks. Glasses from the regolith and the fragmental rocks are divided into six groups : ( 1) diaplectic plagioclase glasses; shock-fused glasses of (2) anorthositic, (3) basaltic low-alkali, (4) basaltic high-alkali, (5) mafic, and (6) granitic compositions. Annealing behavior of fused glasses reveals their rapid cooling on the lunar surface. Two different kinds of annealing behavior have been observed with diaplectic glasses. Rocks of the pre-Imbrian crust, as preserved in the fragmental Fra Mauro formation and in the regolith, are of noritic to anorthositie composition with marie and rhyolitic products of magmatic differentiation and probably also some impact melt rocks fl'om pre-Imbrian impacts. WALKER, D., LO~WGHI, J., AND HAYS, J. F., 1972. Experimental petrology and origin of Fra Mauro rocks and soil. Geochim. Cosmochim. Acta Suppl. 3, 1, 797-817. Melting experiments over the pressure range 0 to 20kbar on Apollo 14 igneous rocks 14310 and 14072, and on comprehensive fines 14259, demonstrate the following: (1) Low pressure crystallization of rocks 14310 and 14072 proceeds as predicted from the textural relationships displayed by thin sections of these rocks. The mineralogy and textures of these rocks are the result of near-surface crystallization. (2) The chemical compositions of these lunar samples all show special relationships to multiply saturated liquids in the system anorthite- forsterite-fayalite-silica at low pressure. (3) Partial melting of a lunar crust consisting largely of plagioclase, low calcium pyroxene, and olivine, followed by crystal fractionation at the lunar surface, is a satisfactory mechanism for the production of the igneous rocks and soil glasses sampled by Apollo 14. The K1REEP component of other lunar softs may have a similar origin.

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WARNER, J . L., 1972. M e t a m o r p h i s m of Apollo 14 breceias. Geochim. Cosmochim. Acta Suppl. 3, 1, 623-643. All Apollo 14 breccias for w h i c h t h i n sections are a v a i l a b l e (27 rocks) were studied petrographically. The samples display a r a n g e in m a t r i x m i n e r a l o g y a n d t e x t u r e f r o m glassy breeeias w i t h a d e t r i t a l m a t r i x , t h r o u g h i n t e r m e d i a t e m e m b e r s w i t h little glass a n d a n a n n e a l e d m a t r i x , to glass-free breccias w i t h a n interlocking, euhedral matrix. Based on the a b u n d a n c e of m a t r i x glass, t h e a b u n d a n c e of glass elasts, a n d t h e m a t r i x t e x t u r e , t h e 27 s a m p l e s are classified i n t o e i g h t g r o u p s f i t t i n g i n t o t h r e e m e t a m o r p h i c grades. O t h e r p e t r o g r a p h i c f e a t u r e s are c o r r e l a t e d w i t h t h i s series. F r o m one s a m p l e in e a c h of six groups, e l e c t r o n m i c r o p r o b e a n a l y s e s were p e r f o r m e d on m a t r i x (less t h a n 25/zm) plagioclase, p y r o x e n e , a n d olivine a n d of r i m s a n d cores of plagioelase a n d p y r o x e n e clasts (50-300/zm). M a t r i x plagioelase, p y r o x e n e , a n d olivine in t h e h i g h - g r a d e rocks d i s p l a y a n a r r o w r a n g e of c o m p o s i t i o n s (approximately An75-80 ; W o s E n 6 0 - s o F s l 5-as ; a n d Fo65_so), s u g g e s t i n g a n e q u i l i b r a t e d or m e t a m o r p h i c origin. H o w e v e r , in t h e l o w - g r a d e rocks a wide r a n g e o f c o m p o s i t i o n s , s u g g e s t i n g a d e t r i t a l or u n e q u i l i b r a t e d origin, is o b s e r v e d . P a r t i a l l y e q u i l i b r a t e d s t a t e s a r e o b s e r v e d in m e d i u m - g r a d e samples. I n h i g h - g r a d e rocks, e s s e n t i a l l y all p y r o x e n e a n d plagioclase elasts d i s p l a y a h o m o g e n e o u s eore a n d a 1-5/~m rim. The rim has the "equilibrated composition" regardless of t h e core c o m p o s i t i o n . I n t h e lowg r a d e rocks n o r i m s were f o u n d , a n d a b o u t h a l f o f t h e clasts in t h e m e d i u m - g r a d e rocks d i s p l a y rims. I t is c o n c l u d e d t h a t t h e Apollo 14 breecias f o r m e d as p a r t of t h e I m b r i u m B a s i n e j e c t s b l a n k e t ~ - t h e F r a M a u r o f o r m a t i o n . T h e cont i n u o u s n a t u r e o f t h e m e t a m o r p h i c series suggests t h a t t h e m e d i u m - a n d h i g h - g r a d e breccias were d e r i v e d f r o m u n m e t a m o r p h o s e d e q u i v a l e n t s b y a u t o m e t a m o r p h i s m in t h e t h i c k , h o t F r a M a u r o f o r m a t i o n a t t h e Apollo 14 site. WATTS, R. N., JR., 1972. More a b o u t Apollo 16. Sky and Telescope 44, 6-13. A p o p u l a r r e v i e w of the lunar and planetary studies phase of the m i s s i o n is p r e s e n t e d w i t h p h o t o g r a p h s . WEIGAND, P. W., AND HOLLISTER, L. S., 1972. P y r o x e n e s f r o m b r e c c i a 14303. Geochim. Cosmochim. Acta Suppl. 3, 1, 471-480. A d j a c e n t p o l i s h e d t h i n sections 47 a n d 53 o f b r e c c i a 14303 h a v e b e e n s t u d i e d . A b a s a l t i c lithic clast, c o m p o s e d m a i n l y o f plagioclase, olivine, a n d p i g e o n i t e z o n e d t o sub-calcic augite, occupies t h e s a m e r e l a t i v e p o s i t i o n in b o t h sections a n d is a s s u m e d t o r e p r e s e n t a single lithic chip. S i m i l a r l y a f r a g m e n t a l clast, c h a r a c t e r i z e d b y

LAYER

109

m i n e r a l clasts of plagioelase, o p a q u e m i n e r a l s , a n d o r t h o p y r o x e n e (En69-s2), is f o u n d in b o t h sections a n d is p r o b a b l y t h e s a m e breccia chip. A s e c o n d f r a g m e n t a l elast, c h a r a c t e r i z e d b y s h o c k e d plagioclase, Mg-rieh b r o n z i t e (Ena6), a n d essential lack of o p a q u e m i n e r a l s > 0 . 0 1 r a m , is f o u n d o n l y in section 53. G r o u n d m a s s p y r o x e n e s are m a i n l y pigeonites a n d augites, a n d are i n t e r p r e t e d as b e i n g f r a g m e n t s of q u i c k l y cooled surface b a s a l t s . O r t h o p y r o x e n e s f r o m 14303 a n d a n o r t h o s i t e 15415 e x h i b i t a l i n e a r c o h e r e n c e of Ti/(Ti + Cr) a n d F s / ( F s + En). This r e l a t i o n ship, plus t h e o b s e r v a t i o n s t h a t 14303 o r t h o p y r o x e n e elasts g e n e r a l l y are l a r g e r t h a n pyroxenes from typical lunar basalts, essentially are u n z o n e d chemically, a n d are d i s t i n c t c h e m i c a l l y f r o m m e t e o r i t i c analogs, suggests t h a t t h e y originally crystallized in a p l u t o n i e m e t a m o r p h i c e n i v o r n m e n t b e n e a t h t h e preI m b r i a n crust. S t u d y of lithic a n d f r a g m e n t a l elasts in breecias p r o b a b l y will yield i n f o r m a t i o n on l u n a r h i s t o r y b e t w e e n 4.6 a n d 3.9b.y. ago.

WENK, ]~., GLAUNER, A., SCItWANDER, H., AND TROSII~ISDORFF, V., 1972. T w i n laws, o p t i c o r i e n t a t i o n , a n d c o m p o s i t i o n of plagioclases f r o m r o c k s 12051, 14053, a n d 14310. Geochim. Cosmochim. Acta Suppl. 3, 1 , 5 8 1 - 5 8 9 . U n i v e r s a l s t a g e s t u d i e s show t h a t l u n a r plagioclases are t w i n n e d a c c o r d i n g t o laws f o u n d in t e r r e s t r i a l feldspars. I n t e r p e n e t r a n t t w i n g r o u p s w i t h symmetrical and pseudosymmetrical mutual o r i e n t a t i o n are c o m m o n . T h e f r e q u e n c y of t h e different t w i n laws c o r r e s p o n d s to t h e e v i d e n c e k n o w n f r o m v o l c a n i c r o c k s of t h e e a r t h . F o r l u n a r b y t o w n i t e s a n d a n o r t h i t e s s i x t y n e w sets of E u l e r I a n g l e s are p r e s e n t e d . T h e s e E u l e r I angles r e l a t e t h e m u t u a l p o s i t i o n s of t h e t h r e e c h i e f v i b r a t i o n d i r e c t i o n s [ h a l , [nil], a n d [ny] of t h e i n d i c a t r i x t o t h e r e c t a n g u l a r cm%esian s y s t e m X = ± [ 1 0 0 ] in (010), Y = (010), a n d Z = [001]. Optical d a t a for l u n a r b y t o w n i t e s are c o n s i s t e n t w i t h t h o s e of t e r r e s t r i a l b y t o w n i t e s . L u n a r a n o r t h i t e s , h o w e v e r , show d i s t i n c t l y higher negative ~ and higher positive ¢ Euler angles t h a n a n o r t h i t e s f r o m y o u n g v o l c a n i c rocks of t h e e a r t h . O p t i c m e a s u r e m e n t s b y different o p e r a t o r s on one a n d t h e s a m e t w i n g r o u p agree w i t h i n 0.5 ° to 1 °. C h e m i c a l i n h o m o g e n e i t y of t h e plagioclases t o w h i c h t h e a u t h o r s ' o p t i c a l d a t a refer is p r o v e n b y m i c r o p r o b e analyses.

WENK, H.-R., ULBRICH, M., A N D

MULLEIn,

W . F., 1972. L u n a r plagioclase: A m i n e r a l o g i c a l s t u d y . Geochim. Cosmochim. Acta Suppl. 3, 1, 569-579. Mineralogical p r o p e r t i e s of calcic plagioclase h a v e b e e n a n a l y z e d u s i n g U - s t a g e , m i c r o p r o b e , X r a y precession c a m e r a s , a n d a 6 5 0 k V e l e c t r o n microscope. T h e o r i e n t a t i o n

110

AFCRL BIBLIOGRAPHY--3RD QUARTER 1972

of t h e optical i n d i c a t r i x in l u n a r a n d e u c r i t e a n o r t h i t e s is d e s c r i b e d w i t h E u l e r angles. All crystals, e x c e p t one, show s t r o n g b- a n d diffuse c-reflections in precession p h o t o g r a p h s . I n 10017, b-split-reflections h a v e b e e n f o u n d . Dark-field e l e c t r o n m i c r o g r a p h s of 14310 a n o r t h i t e show b o t h large a n d small b - a n t i p h a s e d o m a i n s , a n d a n e x s o l u t i o n s t r u c t u r e in c r y s t a l s t h a t d i s p l a y b-split reflections in t h e d i f f r a c t o g r a m . Diffuseness o f c-reflections in X r a y p h o t o g r a p h s a n d t h e i n a b i l i t y t o resolve c - d o m a i n s in electronm i c r o g r a p h s in A n 94 a n o r t h i t e of 14310 i n d i c a t e r e l a t i v e l y r a p i d cooling of t h i s rock c o m p a r e d to p l u t o n i c rocks. WLOTZKA, ]~., JAGOUTZ, E., SPETTEL, B., BADDENHAUSEN, n . , BALACESCU, A., AND WXNKE, H., 1972. On l u n a r m e t a l l i c particles a n d t h e i r c o n t r i b u t i o n to t h e t r a c e e l e m e n t c o n t e n t of Apollo 14 a n d 15 soils. Geochim. Cosmochim. Acta Suppl. 3, 1, 1077-1084. M e t a l particles were s e p a r a t e d f r o m t h e fines 14163 a n d 15601 a n d a n igneous f r a g m e n t of rock 14321. T h e Co a n d Ni c o n t e n t s of a p p r o x i m a t e l y one h u n d r e d i n d i v i d u a l p a r t i c l e s f r o m e a c h s a m p l e were m e a s u r e d . I n t h e 14163 m e t a l , a h i g h p r o p o r t i o n of particles w i t h a m e t e o r i t i c c o m p o s i t i o n are f o u n d , w h i c h are n e a r l y a b s e n t in t h e 15601 m e t a l . B y I N A A , t h e t r a c e e l e m e n t s Cu, Ga, Ge, As, P d , W, Ir, a n d A u were m e a s u r e d in t h e b u l k m e t a l . T h e Co a n d Ni c o n t e n t s a n d t h e siderophile t r a c e e l e m e n t s of t h e " m e t e o r i t i c " 14163 m e t a l c a n be m a t c h e d b y c a r b o n a c e o u s c h o n d r i t e m e t a l or b y h e x a h e d r i t e m e t a l of G a - G e - G r o u p I I - A . T u n g s t e n is e n r i c h e d in t h e m e t a l r e l a t i v e to Ni a b o u t 300 t i m e s o v e r its cosmic a b u n d a n c e . WOLFE, E. ~YV., AND BAILEY, 1~. G., 1972. L i n e a m e n t s of t h e A p e n n i n e F r o n t ~ p o l l o 15 l a n d i n g site. Geochim. Cosmochim. Acta Suppl. 3, 1, 15-25. T h e well-developed s y s t e m s of l i n e a m e n t s t h a t suggest regional f r a c t u r i n g or l a y e r i n g of t h e b e d r o c k in t h e m o u n t a i n s a t t h e Apollo 15 site m a y b e illusions c r e a t e d b y o b l i q u e l i g h t i n g r a t h e r t h a n expressions of t r u e geologic s t r u c t u r e . S u p p o r t i n g e v i d e n c e includes : (1) o c c u r r e n c e of similar d o m i n a n t l i n e a m e n t t r e n d s on m a n y of t h e slopes e v e n t h o u g h t h e slope o r i e n t a t i o n s differ w i d e l y ; (2) p r e s e n c e of a t h i c k m a n t l i n g r e g o l i t h t h a t s h o u l d conceal b e d r o c k s t r u c t u r e s ; (3) a p p r o x i m a t e s y m m e t r y of some of t h e l i n e a m e n t sets a b o u t t h e s u n line ; (4) lack of c l e a r - c u t t o p o g r a p h i c e x p r e s s i o n for m a n y of t h e l i n e a m e n t s ; a n d (5) general s i m i l a r i t y of t h e l u n a r l i n e a m e n t s t o l i n e a m e n t p a t t e r n s p r o d u c e d b y low oblique l i g h t i n g o n m o d e l surfaces m a n t l e d b y fine sifted powder. Locally, as a t Silver Spur, some l i n e a m e n t t r e n d s are r e l a t e d t o d i s t i n c t t o p o g r a p h i c f e a t u r e s a n d are

m o r e c o n f i d e n t l y i n t e r p r e t e d to reflect u n d e r l y i n g geologic s t r u c t u r e s . WOSINSKI, J. F., WILLIAMS, J. P., KORDA, E. J . , KANE, W. T., CAI~,RIER, G. B., AND SCHREURS, J . W. H., 1972. I n c l u s i o n s a n d i n t e r f a c e r e l a t i o n s h i p s b e t w e e n glass a n d breccia in l u n a r s a m p l e 14306,50. Geochim. Cosmochim. Acta Suppl. 3, 1, 853-864. P r e l i m i n a r y o b s e r v a t i o n s of a 2-ram-wide glass-filled f r a c t u r e of breccia s a m p l e No. 14306,50 i n d i c a t e n u m e r o u s s p h e r i c a l inclusions, r a n g i n g f r o m a b o u t 3 0 A to 1 0 0 t t m in size, t o g e t h e r w i t h m a n y voids. T h e inclusions in t h e 0.1 to 1/zm r a n g e are abundant and evenly distributed throughout t h e glass phase, b u t t h e p a r t i c l e s a t t h e l a r g e r a n d smaller e n d s of t h e size r a n g e are m o r e s p a r s e l y d i s t r i b u t e d . T h e s p h e r i c a l bodies are m a i n l y iron-nickel w i t h s e g r e g a t e d zones of i r o n - n i c k e l sulfide (troll±re) a n d iron-nickel p h o s p h i d e (schreibersite), a l t h o u g h some of t h e inclusions a p p e a r to be n e a r l y all sulfide a n d / o r p h o s p h i d e . As m a n y as five m a g n e t i c p h a s e s m a y b e p r e s e n t , a n d t h e r e is e v i d e n c e of single crystal formation. Magnetic analysis indicates m a g n e t i c c e n t e r s as small as 40 to 50A. T h e g l a s s - b r e c c i a i n t e r f a c e is s h a r p l y defined, w i t h t h e t r a n s i t i o n b a n d a p p r o x i m a t e l y 150tL wide. T h e t r a n s i t i o n zone c o n t a i n s a few i r r e g u l a r l y s h a p e d m e t a l l i c inclusions, a m p l e e v i d e n c e o f flow lines a n d m o d e r a t e n u m b e r s of breccia grains w i t h r o u n d e d edges. I s o m e t r i c c o n c e n t r a t i o n m a p s of glass breccia g r a i n i n t e r f a c e s i n d i c a t e n o diffusion of breccia c o n s t i t u e n t s i n t o t h e glass w i t h i n t h e r e s o l u t i o n of t h e e l e c t r o n microprobe. The average chemical composition of t h e glass p h a s e is: SIO2, 46.63 ± 0.24; FeO, 11.60 ± 0.47; N a 2 0 , 0.72 ± 0.04; TiO2, 1.32 ± 0.03; CaO, 8.67 ± 0.35; MgO, 13.53 ± 0.75; A1203, 15.87 ± 0.36; K 2 0 , 0.61 ± 0.04; T o t a l 9 8 . 9 5 w t % . No i n d i c a t i o n of c r y s t a l l i z a t i o n f r o m t h e glass was f o u n d a t t h e i n t e r f a c e or in t h e m a i n b o d y of t h e glass region. T h e s e o b s e r v a t i o n s suggest r a p i d flow a n d cooling o f t h e glass melt. MOON--TEMPERATURE

DUBA, A., HEARD, H . C., AND RCHOCK, R . N., 1972. T h e l u n a r t e m p e r a t u r e profile. Earth Planet. Sci. Lett. 15, 301-304. D a t a o n t h e electrical c o n d u c t i v i t y of a n a t u r a l olivine h a v i n g little or no F e 3+ i n d i c a t e t h a t t h e t e m p e r a t u r e of t h e l u n a r i n t e r i o r c a n b e n e a r t h e solidus of some l u n a r models. MCCONNELL, 1%. K., JR., AND GAST, P. W., 1972. L u n a r t h e r m a l h i s t o r y revisited. The Moon 5, 41-51. T h e i n t e r n a l t e m p e r a t u r e s , h e a t fluxes, a n d r a t e s of e v o l u t i o n of v o l c a n i c liquids

ORIGIN OF THE SOLAR SYSTEM

for l u n a r m o d e l s w i t h initial r a d i o a c t i v i t i e s a n d t e m p e r a t u r e s t h a t decrease going d o w n w a r d i n t h e Moon are c a l c u l a t e d . T h e s e c o n d i t i o n s lead t o a v o l c a n i s m c o n c e n t r a t e d v e r y e a r l y in l u n a r h i s t o r y e v e n w h e n o t h e r h e a t sources, e.g., m e l t i n g d u e to accretion, are e x c l u d e d . MOFFAT, P. H., 1972. A p e r t u r e s y n t h e s i s p o l a r i m e t r y of t h e Moon a t 21 cm. M . N . R. A. S. 169, 139-154. See M o o n - - S u r f a c e L a y e r . PVCH, M. Z., AND BASTIN, J . A., 1972. I n f r a r e d o b s e r v a t i o n s of t h e M o o n a n d t h e i r i n t e r p r e t a t i o n . The M o o n 5, 16-30. See M o o n - Surface L a y e r . SAARI, J . M., AND SHORTHILL, R . W., 1972. T h e s u n l i t l u n a r surface. I. A l b e d o s t u d i e s a n d full m o o n t e m p e r a t u r e d i s t r i b u t i o n . The M o o n 5, 161-178. C e r t a i n s t u d i e s were m a d e of t h e l u n a r surface b a s e d o n m e a s u r e m e n t s a t visible a n d far i n f r a r e d w a v e l e n g t h s o b t a i n e d f r o m a s c a n o v e r t h e full Moon. T h e large n u m b e r of d a t a p o i n t s a v a i l a b l e m a d e it possible t o refine t h e a l b e d o s t a t i s t i c s o v e r t h e disk p r e v i o u s l y d e s c r i b e d b y S y t i n s k a y a (I953). T h e simultaneous measurements at the two wavelengths p r o v i d e d a f a c t o r for c o n v e r t i n g full M o o n p h o t o m e t r i c b r i g h t n e s s to b o l o m e t r i c albedo. T h e d i s k - a v e r a g e d v a l u e of t h i s p a r a m e t e r is consistent with previous photometric measurements. The brightness temperature statistics o v e r t h e disk led t o a r e p l a c e m e n t of t h e t r a d i t i o n a l cos 1/~ 0 law of t e m p e r a t u r e v a r i a t i o n o v e r t h e full M o o n b y a n e x p r e s s i o n w h i c h is l i n e a r in cos 0. SAARI, J . M., SHORTHILL, R . W., AND WINTER, D. F., 1972. T h e s u n l i t l u n a r surface. I I . A s t u d y o f f a r i n f r a r e d b r i g h t n e s s t e m p e r a t u r e s . The M o o n 5, 179-199. D i r e c t i o n a l i n f r a r e d emission f r o m t h e s u n l i t l u n a r surface is d e t e r m i n e d for t h e t h e r m a l m e r i d i a n a n d as a f u n c t i o n of o b s e r v e r e l e v a t i o n a n d a z i m u t h angles a t t h r e e S u n e l e v a t i o n angles. A s t u d y o f selected m a r e sites a t full M o o n suggests t h a t b r i g h t n e s s t e m p e r a t u r e s are r e l a t i v e l y i n s e n s i t i v e t o c h a n g e s in c e r t a i n surface p a r a m e t e r s , s u c h as t h e p h o t o metric function, emissivity, and thermophysical p r o p e r t i e s o f t h e soil. T h e o b s e r v e d d e v i a t i o n s f r o m p r e d i c t i o n s for a n " a v e r a g e " surface c a n b e a c c o u n t e d for b y c h a n g e s in surface r o u g h n e s s . T o x s 6 z , M. N., SOLOMON, S. C., MINEAR, J . W., AND JOHNSTON, D. H . , 1972. A d d e n d u m and Erratum to the paper "Thermal Evolution o f t h e M o o n " . The M o o n 5, 231-232. T h e h e a t flow v a l u e s l i s t e d in T a b l e I of t h e p a p e r " T h e r m a l E v o l u t i o n of t h e M o o n " p u b l i s h e d i n The M o o n 4 (1972), 190-213, are incorrect. A n e w t a b l e is g i v e n w h i c h lists t h e original a n d t h e c o r r e c t e d h e a t flow values. TOZER, D. C., 1972. T h e M o o n ' s t h e r m a l s t a t e

l 11

a n d a n i n t e r p r e t a t i o n of t h e l u n a r electrical c o n d u c t i v i t y d i s t r i b u t i o n . The M o o n 5, 90-105. H e a t c o n v e c t i o n , b e i n g a m o r e general t h e o r y t h a n c o n d u c t i o n t h e o r y , compels one to give r e a s o n s for u s i n g t h e l a t t e r t h e o r y as t h e basis of t h e r m a l e v o l u t i o n studies. S u c h r e a s o n s are s u p p l i e d b y c o n s i d e r a t i o n s of m a t e r i a l rheolcgy. T h e specific case of t h e t h e r m a l r e g i m e of t h e M o o n is first c o n s i d e r e d as a s t e a d y s t a t e p r o b l e m . I t is d e m o n s t r a t e d t h a t no p l a u s i b l e creep r e s i s t a n c e of l u n a r m a t e r i a l a n d h e a t g e n e r a t i o n is c o m p a t i b l e w i t h a p u r e l y cond u c t i v e t h e o r y of l u n a r t h e r m a l e v o l u t i o n . T h e m o s t plausible, s t e a d y s t a t e m o d e l s give conv e c t i v e cores e x t e n d i n g t o w i t h i n 2 0 0 - 3 0 0 k i n of t h e surface. T h e r a d i a l t e m p e r a t u r e g r a d i e n t s i n s u c h cores is v i r t u a l l y confined to a t h e r m a l b o u n d a r y l a y e r b u t a v e r a g e s to a b o u t a t e n t h of d e g r e e / k m . T h e (steady) c e n t r a l t e m p e r a t u r e for t h e m o s t p l a u s i b l e l u n a r rbeologies lie b e t w e e n 600-1000°C. Such m o d e l s are comp a t i b l e w i t h t h e first i n t e r p r e t a t i o n s o f l u n a r I n a g n e t o m c t r y . T h e case for c o n s i d e r i n g t h e l u n a r t h e r m a l s t a t e as s u c h a q u a s i s t a t i c s t a t e is discussed. I t is also p r e d i c t e d t h a t in v e r y local zones t h e viscous d i s s i p a t i o n of t h e general circulation produces much higher temperatures. Chemical differentiation and seismicity would h a v e t h e i r origin in such low v i s c o s i t y zones.

ORIGIN

OF THE

SOLAR SYSTEM

ALFV]~N, H . , AND ARR~IENIUS, G., 1972. Origin a n d e v o l u t i o n of t h e E a r t h - M o o n s y s t e m . The M o o n 5, 210-230. T h e origin a n d e v o l u t i o n of t h e E a r t h - M o o n s y s t e m is s t u d i e d b y comp a r i n g it to t h e satellite s y s t e m s of o t h e r p l a n e t s . T h e n o r m a l s t r u c t u r e of a s y s t e m of s e c o n d a r y bodies o r b i t i n g a r o u n d a c e n t r a l b o d y d e p e n d s e s s e n t i a l l y o n t h e m a s s of t h e c e n t r a l b o d y . T h e E a r t h w i t h a m a s s inteITnediate b e t w e e n U r a n u s a n d Mars s h o u l d h a v e a " n o r m a l " s a t e l l i t e s y s t e m t h a t consists of a b o u t h a l f a d o z e n satellites e a c h w i t h a m a s s of a f r a c t i o n of a p e r c e n t of t h e l u n a r m a s s . H e n c e , t h e M o o n is n o t likely to h a v e b e e n g e n e r a t e d in t h e e n v i r o n m e n t of t h e E a r t h b y a n o r m a l a c c r e t i o n process as is c l a i m e d b y some a u t h o r s . C a p t u r e of satellites is q u i t e a c o m m o n process as s h o w n b y t h e f a c t t h a t t h e r e are six satellites in t h e solar s y s t e m w h i c h , b e c a u s e t h e y are r e t r o g r a d e , m u s t h a v e b e e n c a p t u r e d . T h e r e is l i t t l e d o u b t t h a t t h e M o o n is also a c a p t u r e d satellite, b u t its c a p t u r e o r b i t a n d t i d a l e v o l u t i o n are still incompletely understood. The Earth and the M o o n are likely t o h a v e b e e n f o r m e d f r o m planetesimals accreting in particle swarms in

112

AFCRL B I B L I O G R A P H Y - - 3 R D QUARTER 1 9 7 2

K e p l e r o r b i t s ( j e t streams). T h i s process leads to t h e f o r m a t i o n of a coot l u n a r i n t e r i o r w i t h a n outer layer accreted at increasingly higher temperatures. The primeval Earth should s i m i l a r l y h a v e f o r m e d w i t h a cool i n n e r core s u r r o u n d e d in t h i s case b y a v e r y s t r o n g l y h e a t e d o u t e r core a n d w i t h a m a n t l e a c c r e t e d slowly a n d w i t h a low a v e r a g e t e m p e r a t u r e h u t with intense transient heating at each individual i m p a c t site. H~IAN~, W . K., 1972. P a l e o c r a t e r i n g of t h e M o o n : R e v i e w of p o s t -Apollo d a t a . Astrophys. Space Sci. 17, 48-64. See M o o n - - S u r f a c e Features. KERR[D~E, J . F., AND VEDDER, J . F., 1972. A c c r e t i o n a r y processes in t h e e a r l y solar s y s t e m : A n e x p e r i m e n t a l a p p r o a c h . Science 177, 161-163. Micrometer-size silicate flakes do n o t a c c r e t e d u r i n g i m p a c t s in t h e v e l o c i t y r a n g e 1.5 t o 9.5 k i l o m e t e r s p e r second. C o n v e n t i o n a l accret i o n a r y t h e o r i e s for silicate bodies are a p p l i c a b l e o n l y to p a r t i c l e s w h o s e o r b i t s are similar. Metal-silicate f r a c t i o n a t i o n in t h e solar s y s t e m m a y h a v e b e e n affected b y differences in t h e a c c r e t i o n a r y b e h a v i o r of t h e m e t a l a n d silicate particles. L E w m , J . S., 1972. Metal/silicate f r a c t i o n a t i o n in t h e solar s y s t e m . Earth Planet. Sci. Lett. 15, 286-290. F r a c t i o n a t i o n b e t w e e n t h e m e t a l a n d silicate c o m p o n e n t s of o b j e c t s in t h e i n n e r solar s y s t e m h a s long b e e n recognized as a n e c e s s i t y in o r d e r to e x p l a i n t h e o b s e r v e d d e n s i t y varia t i o n s of t h e t e r r e s t r i a l p l a n e t s a n d t h e H - g r o u p , L - g r o u p d i c h o t o m y of t h e o r d i n a r y c h o n d r i t e s . T h i s p a p e r discusses t h e d e n s i t i e s of t h e terrest r i a l p l a n e t s in l i g h t of c u r r e n t p h y s i c a l a n d c h e m i c a l m o d e l s of processes in t h e solar n e b u l a . I t is s h o w n t h a t t h e o b s e r v e d d e n s i t y t r e n d s in t h e i n n e r solar s y s t e m n e e d n o t be t h e r e s u l t of special f r a c t i o n a t i o n processes, a n d t h a t t h e d e n s i t i e s of t h e p l a n e t s m a y b e d i r e c t results of s i m u l t a n e o u s a p p l i c a t i o n of b o t h p h y s i c a l a n d c h e m i c a l r e s t r a i n t s o n t h e s t r u c t u r e of t h e n e b u l a , m o s t n o t a b l y t h e v a r i a t i o n of t e m p e r a t u r e w i t h h e l i o c e n t r i c d i s t a n c e . T h e d e n s i t y of M e r c u r y is easily a t t r i b u t e d to a c c r e t i o n a t t e m p e r a t u r e s so h i g h t h a t MgSiO a is o n l y part i a l l y r e t a i n e d b u t F e m e t a l is c o n d e n s e d . T h e densities of t h e o t h e r t e r r e s t r i a l p l a n e t s are s h o w n to b e d u e t o different degrees of r e t e n t i o n of S, O a n d H as FeS. F e O a n d h y d r o u s silicates produced in chemical equilibrium between e o n d e n s a t e s a n d s o l a r - c o m p o s i t i o n gases. I t is p r o p o s e d t h a t M e r c u r y a n d V e n u s h a v e cores of F e °*, E a r t h h a s a core of F e ° c o n t a i n i n g s u b s t a n t i a l a m o u n t s of FeS, a n d M a r s h a s a q u i t e s m a l l core of F e S w i t h m o r e F e O in its * F e ° -- m e t a l l i c iron.

m a n t l e t h a n in E a r t h ' s . G e o p h y s i c a l a n d geoc h e m i c a l c o n s e q u e n c e s of t h e s e conclusions are discussed. POLYACItENKO, V. L., AND FRIDMAN, A. M., 1972. T h e law of p l a n e t a r y distances. Sov. A s t r o n . - - A J 16, 123-128. T h e s t a b i l i t y of t h e p r o t o p l a n e t a r y - c l o u d m o d e l for t h e solar s y s t e m as a flat disk of gas a n d d u s t is i n v e s t i g a t e d . A n initial profile is o b t a i n e d for t h e surface d e n s i t y of t h e disk s u c h t h a t g r o w i n g a x i s y m m e t r i c d e n s i t y p e r t u r b a t i o n s will o c c u p y t h e sites of t h e p l a n e t a r y orbits. T h e surface d e n s i t y w o u l d h a v e declined ~ 1/r 2 for r < 14 a.u., a n d ~ 1/r 3 b e y o n d . A criterion is d e r i v e d for g r a v i t a t i o n a l s t a b i l i t y of t h e gas -dust disk, i n d i c a t i n g t h a t t h e p l a n e t s t o d a y c o m p r i s e n o m o r e t h a n 3 % of t h e m a s s of t h e p r o t o p l a n e t a r y cloud. Possible mass-loss m e c h a r / i s m s are discussed. SINGER, S. F., 1972. Origin o f t h e Moon b y t i d a l c a p t u r e a n d some g e o p h y s i c a l consequences. The M o o n 5, 206-209. See M o o n - - G e n e r a l . WItITE, M. L., 1972. J e t s t r e a m s a n d t h e d e v e l o p m e n t of t h e solar s y s t e m . Nature 238, 105 106. H y d r o d y n a m i c c o n s i d e r a t i o n s show t h a t j e t s t r e a m s c a n d e v e l o p in a r o t a t i n g gaseous disk o n l y a t c e r t a i n discrete o r b i t a l distances. F o r e v e r y d i s c r e t e z o n a l jet, t h e r e will b e one a n d o n l y one r o t a t i n g s u b s y s t e m , a v o r t e x w i t h a n e n r i c h e d core. T h e r o t a t i n g s u b s y s t e m will f l a t t e n out, b e c o m e a n a s y m m e t r i c r o t a t o r , a n d d e v e l o p j e t s t r e a m s , so t h a t t h e s u b s y s t e m itself could d e v e l o p into a p l a n e t w i t h o r b i t i n g s a t e l l i t e s - - a m i n i a t u r e solar system. The transition from the hydrodynamic r e g i m e of a r o t a t i n g p r i m o r d i a l gas to K e p l e r i a n o r b i t s o b t a i n s b e c a u s e in t h e l i m i t t h e e q u a t i o n of fluid d y n a m i c s reduces to t h e law of p a r t i c l e d y n a m i c s , t h a t is, t h e E u l e r i a n a n d L a g r a n g i a n derivatives become equivalent. WILLIAMS, G. E., 1972. Geological e v i d e n c e r e l a t i n g t o t h e origin a n d secular r o t a t i o n o f t h e solar s y s t e m . Mod. Geol. 3, 165-181. T h e E a r t h ' s glacial, s e d i m e n t a r y , pedological, biological a n d g e o m a g n e t i c records p r o v i d e s t r o n g e v i d e n c e for secular c h a n g e in t h e o b l i q u i t y of t h e ecliptic. I t is d e d u c e d f r o m p e r i o d i c i t y of t h e secular c h a n g e t h a t a t t h e t i m e of t h e E a r t h ' s f o r m a t i o n a p p r o x i m a t e l y 4500 million y e a r s ago t h e spin axis l a y in t h e o r b i t a l plane. Moreover, P a l a e o zoic p a l a e o n t o l o g i c a l " c l o c k s " p r o v i d e e v i d e n c e for a f o r m e r m o r e r a p i d spin of t h e E a r t h . T h e s e reconstructed dynamic elements of the primeval E a r t h l e a d to a n e w h y p o t h e s i s for t h e origin of t h e solar s y s t e m , w h i c h e n v i s a g e s t h e p l a n e t s a n d satellites c o n d e n s i n g f r o m a n a t t e n u a t e d , t o r n a d o - l i k e p r o m i n e n c e or j e t of gases e j e c t e d f r o m t h e p r i m e v a l Sun. Secular c h a n g e in t h e o b l i q u i t y o f t h e p l a n e t s ' s p i n axes is a t t r i b u t e d

PLANETS--JUPITER to secular r o t a t i o n , w i t h a p e r i o d of a p p r o x i m a t e l y 2500 million years, of t h e p l a n e of t h e solar s y s t e m , t h e s p i n n i n g p l a n e t s a c t i n g as gyroscopes a n d t e n d i n g to m a i n t a i n t h e i r a t t i t u d e s in space d u r i n g s u c h r o t a t i o n . WILLIAMS, I. P., 1972. T h e floccule t h e o r y for p l a n e t a r y f o r m a t i o n . Astrophys. Space Sci. 18, 223-225. T h e a c c u m u l a t i o n of floccules i n t o p r o t o p l a n e t s is discussed, a n d i t is p o i n t e d o u t t h a t t h e simplifications w h i c h h a v e b e e n introduced into recent numerical models may r e s u l t in t h e i n c o r r e c t conclusion b e i n g r e a c h e d .

PLANETS--GENERAL

ALEKSANDROV, Y c . N., KUZ~ETSOV, B. I., PETROV, G. M., AND RZHIGA, O. N., 1972. T e c h n i q u e s of r a d a r a s t r o m e t r y . Sov. Astron.-A J 16, 137-144. T h e r a d a r o b s e r v a t i o n s of t h e p l a n e t s d u r i n g t h e p a s t d e c a d e h a v e b e e n of c a r d i n a l i m p o r t a n c e i n refining t h e v a l u e of t h e a s t r o n o m i c a l u n i t , b u t e v e n a f t e r c o r r e c t i o n s are applied, significant discrepancies r e m a i n b e t w e e n t h e a c t u a l positions of t h e p l a n e t s r e l a t i v e t o t h e earth and those calculated from the analytic t h e o r y . T h u s , t h e r e f i n e m e n t of p l a n e t a r y orbital elements represents a paramount task facing r a d a r a s t r o m e t r y . A d e s c r i p t i o n is g i v e n of t e c h n i q u e s for m e a s u r i n g t h e d i s t a n c e a n d r a d i a l v e l o c i t y of p l a n e t s , as d e v e l o p e d d u r i n g 1965-1969 a t t h e I n s t i t u t e of R a d i o E n g i n e e r i n g . T h e basic d e s i g n principles of t h e r a d a r equipm e n t arc discussed. T h e errors of m e a s u r e m e n t are e s t i m a t e d for r a d a r o b s e r v a t i o n s of Venus. iRKING, A., AND GROSSMAN, K., 1972. T h e influence of line s h a p e a n d b a n d s t r u c t u r e o n t e m p e r a t u r e s in p l a n e t a r y a t m o s p h e r e s . J . Atmos. Sci. 29, 937-949. N u m e r i c a l e x p e r i m e n t s are p e r f o r m e d to e x a m i n e t h e effects of line shape and band structure on the radiative e q u i l i b r i u m t e m p e r a t u r e profile in p l a n e t a r y atmospheres. In order to accurately determine t h e s e effects, a m e t h o d for c a l c u l a t i n g r a d i a t i v e t e r m s is d e v e l o p e d w h i c h a v o i d s t h e u s u a l a p p r o x i m a t i o n s . I t differs f r o m t h e m o r e c o m m o n l y u s e d m e t h o d s in t h a t i t allows a r b i t r a r y d e p e n d e n c e o f t h e a b s o r p t i o n coefficient o n w a v e n u m b e r , w i t h o u t r e q u i r i n g t e d i o u s line-by-line i n t e g r a t i o n a n d w i t h o u t t h e c o n s t r a i n t s of b a n d models. T h e p r e s e n t f o r m u l a t i o n is r e s t r i c t e d t o h o m o g e n e o u s a t m o s p h e r e s but the concept can be extended to the more general case. T h e n u m e r i c a l e x p e r i m e n t s r e v e a l t h a t t h e line s h a p e a n d b a n d s t r u c t u r e of t h e a b s o r b i n g gases h a v e a large effect o n t e m p e r a t u r e s in t h e h i g h e r l a y e r s of t h e a t m o s p h e r e ( c o r r e s p o n d i n g t o t h e s t r a t o s p h e r e a n d meso-

1 13

sphere). T h e m o r e n o n - g r e y t h e s p e c t r u m , i.e., the higher the peaks and the deeper the troughs in t h e s p e c t r u m , t h e lower t h e t e m p e r a t u r e . F o s s , A. P. 0 . , SHAWE-TAYLOR, J . S., AND WHITWORTH, D. P. D., 1972. S e a r c h for a t r a n s P l u t o n i a n p l a n e t . Nature 239, 266. T h e a u t h o r s h a v e c o n d u c t e d a s e a r c h for t h e t r a n s - P l u t o n i a n p l a n e t p r e d i c t e d b y B r a d y . No m o v i n g o b j e c t b r i g h t e r t h a n m a g n i t u d e 15.5 was f o u n d . SOBOLEV, V. V., 1972. O n t h e t h e o r y of p l a n e t a r y s p e c t r a . Soy. A s t r o n . - - A J 16, 324-330. T h e profiles a n d e q u i v a l e n t w i d t h s of a b s o r p t i o n lines are d e t e r m i n e d for t w o cases: (1) a n a t m o s p h e r e of small optical d e p t h , b o u n d e d b y a reflecting s u r f a c e ; (2) a semi-infinite a t m o s p h e r e w i t h small t r u e a b s o r p t i o n . A n a r b i t r a r y s c a t t e r i n g i n d i c a t r i x is p e r m i t t e d .

PLANETS--JUPITER BHATTACHARYYA, J . C., 1972. O c c u l t a t i o n of B e t a Scorpii b y J u p i t e r on M a y 13, 1971. Nature 238, 55-56. T h e l i g h t c u r v e shows a few flashes l a s t i n g for 2 - 4 s , w h e n t h e s t a r is v e r y close to t h e J o v i a n l i m b . A series of l i g h t c u r v e s for a t m o s p h e r e s w i t h v a r y i n g scale h e i g h t s a n d w i t h t h e v e l o c i t y p a r a m e t e r s for t h e p r e s e n t o c c u l t a t i o n were c o m p u t e d , a n d t h e o b s e r v e d p o i n t s on t h e l i g h t c u r v e c o r r e l a t e d w i t h these. T h e b e s t fit is seen to occur for a scale h e i g h t a r o u n d 3 k i n . C o m b i n i n g t h e scale h e i g h t d e r i v e d a b o v e w i t h t h e p h y s i c a l p a r a m e t e r s of Jupiter's atmosphere adopted by Baum and Code, t h e m e a n m o l e c u l a r w e i g h t of t h e J o v i a n atmosphere comes out as 9. A temperature higher than the assumed value of 86K will lower the computed mean molecular weight; the more recent estimate of 150K gives a mean molecular weight of 5. If, however, a predominantly hydrogen atmosphere is assumed, the temperatures of the refracting layers must be around 500K to explain the observed light curve. CHAPRONT, J., AND SIMON, J. L., 1972. Secular v a r i a t i o n s of t h e first order, for t h e four m a j o r p l a n e t s . C o m p a r i s o n w i t h Le V e r r i e r a n d Gaillot. Astron. Astrophys. 19, 231-234. T h e authors present the results they have obtained for t h e secular v a r i a t i o n s o f t h e o s c u l a t i n g e l e m e n t s (a, e, ~, 2, ~ , .Q) for t h e m a j o r p l a n e t s of t h e Solar s y s t e m , J u p i t e r , S a t u r n , U r a n u s , a n d Neptune. The four planets are taken all together; t h e first o r d e r o n l y w i t h r e s p e c t t o t h e d i s t u r b i n g m a s s e s is considered, i n view o f a c o m p a r i s o n w i t h t h e results of Le V e r r i e r (1876) a n d Gaillot (1910). T h r e e sets o f results are g i v e n in t a b l e (2). I n (c) of t a b l e (2) m o d e r n v a l u e s of

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AFCRL B I B L I O G R A P H Y - - 3 R D QUARTER 1972

t h e c o n s t a n t s of i n t e g r a t i o n a n d of t h e m a s s e s h a v e b e e n u s e d (table 2b). T h e discrepancies b e t w e e n (b) a n d (c) are discussed. T h e a u t h o r s suggest a r e v i s i o n for t h e secular v a r i a t i o n s w h i c h are g i v e n i n t h e E p h e m e r i d e s . (In French.) CODE, A. D., AND SAVAGE, B. D., 1972. Orbiting astronomical observatory: Review of scientific results. Science 177, 213-221. See Comets. CR]JIKSI-IA=NK, D. P., A=NDMORRISON, D., 1972. T i t a n a n d its a t m o s p h e r e . Sky and Telescope 44, 83-85. T h e a u t h o r s r e v i e w p a s t o b s e r v a t i o n s of T i t a n a n d p r e s e n t t h e i r results w h i c h i n d i c a t e a n o m a l o u s l y low t e m p e r a t u r e s a t 2 0 ~ m , w h i c h suggests a " g r e e n h o u s e " effect i n t h e a t m o s phere. I t is also s u g g e s t e d t h a t t h e a t m o s p h e r e of T i t a n m a y r e s e m b l e t h a t of S a t u r n . FAIR_~LL, A. P., 1972. S y m m e t r y of flashes d u r i n g t h e J o v i a n o c c u l t a t i o n of fi Scorpii. Nature 236, 342. W h e n J u p i t e r o c c u l t e d t h e b r i g h t s t a r f~ Scorpii A on M a y 13, 1971, a n u m b e r of s p e c t a c u l a r flashes a c c o m p a n i e d t h e f a d i n g a n d b r i g h t e n i n g of t h e s t a r as it p a s s e d b e h i n d t h e p l a n e t ' s disk a n d was o b s e r v e d through the Jovian atmosphere. Filmed observat i o n s show t h a t t h e flashes a t t h e t i m e of t h e d i s a p p e a r a n c e are t i m e - s y m m e t r i c w i t h t h o s e d u r i n g t h e r e a p p e a r a n c e . T h e flashes are p r e s u m a b l y p r o d u c e d b y t o t a l i n t e r n a l reflexion b e t w e e n a t m o s p h e r i c layers. T h u s t h e s e observat i o n s i m p l y global s t r a t i f i c a t i o n , r a t h e r t h a n local effects, in t h e J o v i a n a t m o s p h e r e . F o x , K . , OWEN, T., MA=N~z, A. W., A=NDRAO, K . N., 1972. A t e n t a t i v e i d e n t i f i c a t i o n of 13CH4 a n d a n e s t i m a t e of 12C#3C in t h e a t m o s p h e r e of J u p i t e r . Ap. J. 176, L 8 1 - L 8 4 . ~3CH4 h a s b e e n identified in t h e a t m o s p h e r e of t h e p l a n e t J u p i t e r b y c o m p a r i s o n of several J - m u l t i p l e t s i n n e w l a b o r a t o r y a n d J o v i a n s p e c t r a of t h e 3 ~3 b a n d a t 1.1/zm. F r o m t h e e q u i v a l e n t w i d t h of R{2), m e a s u r e d o n t h e t w o b e s t s p e c t r o g r a m s , a J o v i a n 12C/13C isotopic a b u n d a n c e r a t i o of 110 J= 35 h a s b e e n d e r i v e d . GOLDSTEI:N, M. L., A=ND EVIATAR, A., 1972. T h e p l a s m a physics of t h e J o v i a n d e c a m e t e r r a d i a t i o n . The Ap. J. 175, 275-283. T h e a s s u m p t i o n is m a d e t h a t t h e d e c a m e t e r r a d i a t i o n f r o m J u p i t e r is p r o d u c e d n e a r t h e local e l e c t r o n g y r o f r e q u e n c y a n d is amplified as it p r o p a g a t e s o u t of t h e J o v i a n m a g n e t o s p h e r e . U s i n g t h e V l a s o v - M a x w e l l e q u a t i o n s , t h e g r o w t h r a t e for radiation that propagates almost perpendicular t o t h e d i r e c t i o n of t h e m a g n e t i c field is d e r i v e d . W h e n t h e electrons are d e s c r i b e d b y a loss-cone d i s t r i b u t i o n f u n c t i o n , t h e g r o w t h r a t e is large e n o u g h t o lead to a large a m p l i f i c a t i o n f a c t o r o v e r a source region of 1 0 0 - 4 0 0 0 k i n , d e p e n d i n g

on t h e choice of p a r a m e t e r s . B e c a u s e low-energy electrons are e x p e c t e d to b e t r a p p e d i n t h e J o v i a n dipole field regardless of t h e p o s i t i o n of t h e satellite Io, it is m a i n t a i n e d t h a t t h i s m o d e l p r o v i d e s a plausible m e c h a n i s m for t h e decam e t r i c r a d i a t i o n n o t associated w i t h Io. GRUBF.R, G. M., WAY-Jo=NEs, C., 1972. S t r o n g b e a m i n g of J u p i t e r ' s n o n - I o - r e l a t e d radio emission. Nature 237, 137-139. W i t h i n one m o n t h of o p p o s i t i o n t h e p e r c e n t a g e p r o b a b i l i t y of receiving a n y d e c a m e t r i c r a d i a t i o n is a l m o s t h a l v e d . I t a p p e a r s t h a t I o - r e l a t e d sources r a d i a t e fairly c o n s t a n t l y t h r o u g h o u t a n a p p a r i t i o n w h e r e a s t h e n o n - I o - r e l a t e d sources h a v e a fairly s h a r p cut-off a f t e r opposition. T h i s difference in t h e r a d i a t i o n c h a r a c t e r i s t i c s suggests t h a t t h e r e are t w o c o m p o n e n t s of J o v i a n decametric radiation. GURNETT, D. A., 1972. S h e a t h effects a n d related charged-particle acceleration by Jupiter's satellite Io. Ap. J. 175, 525-533. Several c u r r e n t t h e o r i e s on t h e J o v i a n d e c a m e t r i c r a d i o emission, a n d its m o d u l a t i o n b y t h e satellite Io, assume that the plasma within the magnetic flux t u b e passing t h r o u g h Io is " f r o z e n " to t h e m o t i o n of Io. T h i s p a p e r considers t h e effects of t h e p l a s m a s h e a t h a r o u n d Io o n t h e i n t e r a c t i o n of Io w i t h t h e J o v i a n m a g n e t o s p h e r e . I t is f o u n d t h a t u n d e r some c o n d i t i o n s t h e p l a s m a s h e a t h a r o u n d Io c a n effectively i n s u l a t e t h e magnetospheric plasma from the motional electric field g e n e r a t e d w i t h i n Io, t h u s p r e v e n t i n g t h e p l a s m a f r o m b e i n g frozen t o t h e m o t i o n of Io. U n d e r t h e s e c o n d i t i o n s large p o t e n t i a l s are d e v e l o p e d across t h e p l a s m a s h e a t h a n d e m i t t e d photoelectrons can be accelerated to high energies. T h e s h e a t h v o l t a g e s w h i c h d e v e l o p are c o n t r o l l e d b y t h e ionospheric c o n d u c t i v i t y a t t h e base of t h e Io flux t u b e , as well as o t h e r p l a s m a p a r a m e t e r s a t Io. A simplified m o d e l i l l u s t r a t i n g t h e s e basic effects is discussed. HUBBARD, W. B., 1972. S t a t i s t i c a l m e c h a n i c s of l i g h t e l e m e n t s a t h i g h pressure. I I . H y d r o g e n a n d h e l i u m alloys. The Ap. J. 176, 525-531. A M o n t e Carlo m e t h o d d e s c r i b e d in a p r e v i o u s p a p e r is u s e d to e v a l u a t e v a r i o u s t h e r m o d y n a m i c q u a n t i t i e s for h y d r o g e n - h e l i u m m i x t u r e s a t t e m p e r a t u r e s a n d pressures c h a r a c t e r i s t i c o f t h e J o v i a n interior. T h e a d d i t i v e - v o l u m e l a w for chemical mixtures appears to be an excellent a p p r o x i m a t i o n . H o w e v e r , t h e D e b y e e q u a t i o n of s t a t e for t h e t e m p e r a t u r e d e p e n d e n c e of t h e p r e s s u r e is r a t h e r c r u d e a n d t e n d s to overe s t i m a t e t h e p r e s s u r e for a g i v e n t e m p e r a t u r e and density. HUNTE=N, D. M., 1972. T h e a t m o s p h e r e of T i t a n . Comm. Astrophys. Space Phys. 4, 149-154. T h e s t a t e of k n o w l e d g e of t h e a t m o s p h e r e a n d

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p h y s i c a l c h a r a c t e r i s t i c s of J u p i t e r ' s satellite T i t a n are reviewed. KLEIN, M. J . , GULKIS, S., AND STELZRIED, C. T., 1972. J u p i t e r : N e w e v i d e n c e of l o n g - t e r m v a r i a t i o n s of its d e c i m e t e r flux d e n s i t y . Ap. J. 176, L 8 5 - L 8 8 . J u p i t e r ' s flux d e n s i t y a t 1 2 . 6 c m was m e a s u r e d a t weekly i n t e r v a l s f r o m 1971 May through October. When compared with previous dccimetric measurements, these data i n d i c a t e t h a t J u p i t e r ' s t o t a l flux d e n s i t y h a s d e c r e a s e d a p p r o x i m a t e l y 2 0 % since 1964. No s h o r t - t e r m v a r i a t i o n s g r e a t e r t h a n a few p e r c e n t were o b s e r v e d . MAXWORTHY, T., 1972. C o m m e n t s o n " A M e c h a n i s m for J u p i t e r ' s E q u a t o r i a l Accelerat i o n " . J. Atmos. Sci. 29, 1007-1008. T h e m e c h a n i s m p r o p o s e d b y G i e r a s c h a n d S t o n e (1968) to a c c o u n t for t h e e q u a t o r i a l j e t f o u n d h i g h in t h e J o v i a n a t m o s p h e r e h a s r e c e n t l y b e e n criticized b y H i d e . I n t h i s n o t e t h e a u t h o r a d d s one more comment which casts further doubt on t h e v a l i d i t y of t h e G i e r a s c h - S t o n e (G-S) p i c t u r e . I t is b a s e d m o r e d i r e c t l y o n t h e fluid d y n a m i c a l processes i n v o k e d b y G-S a n d less o n general c o n s i d e r a t i o n s , as p r e s e n t e d b y H i d e . V e r y s i m p l y s t a t e d , t h e a u t h o r believes t h a t t h e flow p a t t e r n s h o w n i n t h e G-S p a p e r is u n a b l e to t r a n s p o r t a n g u l a r m o m e n t u m across t h e b o u n daries of t h e m e r i d i o n a l cells of t h e s y m m e t r i c baroclinic i n s t a b i l i t y . I n a reply, G i e r a s c h a n d Stone state that Maxworthy's statement that a n g u l a r m o m e n t u m will n o t b e t r a n s p o r t e d across t h e cell b o u n d a r i e s of t h e flow p a t t e r n discussed in t h e i r n o t e (Gierasch a n d Stone, 1968), a n d t h e r e f o r e will n o t b e t r a n s p o r t e d f r o m t h e cool e n d t o t h e h o t e n d of t h e s y s t e m , is correct. H o w e v e r , t h e whole p o i n t of t h e a u t h o r s ' n o t e was t h a t t h e m o m e n t u m w o u l d b e t r a n s p o r t e d e q u a t o r w a r d . Since t h e cell b o u n d a r i e s are parallel t o t h e i s o t h e r m s of p o t e n t i a l t e m p e r a t u r e a n d are sloping t h e r e is no contradiction between these two statements. MOLTON, ]~., AND PONNAMPERUMA, C., 1972. S u r v i v a l of c o m m o n t e r r e s t r i a l m i c r o o r g a n i s m s u n d e r s i m u l a t e d J o v i a n c o n d i t i o n s . Nature 238, 217-218. T h e s u r v i v a l of m i c r o o r g a n i s m s u n d e r simulated Jovian conditions indicates that there is a v e r y real possibility of t h e c o n t a m i n a t i o n o f Jupiter by a nonsterile spacecraft, provided that t h e p l a n e t c a n also p e r m i t g r o w t h of s u c h c o n t a m i n a n t s . T h e a p p a r e n t ease w i t h w h i c h some v e r y c o m m o n o r g a n i s m s c a n s u r v i v e for 2 4 h r suggests t h a t , w i t h a d a p t a t i o n , g r o w t h of anaerobic organisms may be a probability. REEVES, H . , AND BOTTINGA, Y., 1972. T h e D / H r a t i o i n J u p i t e r ' s a t m o s p h e r e . Nature 238, 326-327. A t h e o r e t i c a l e s t i m a t i o n is m a d e of t h e D / H r a t i o in J u p i t e r ' s a t m o s p h e r e .

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TAYLOR, F. W., 1972. T e m p e r a t u r e s o u n d i n g e x p e r i m e n t s for t h e J o v i a n p l a n e t s . J. Atmos. Sei. 29, 950-958. T h e possibilities for v e r t i c a l temperature sounding experiments by mediumr e s o l u t i o n m e a s u r e m e n t s of o u t g o i n g r a d i a n c e are e x a m i n e d for n o n s c a t t e r i n g models of J u p i t e r , S a t u r n , U r a n u s a n d N e p t u n e . I t is s h o w n t h a t for J u p i t e r t h e w i d e s t v e r t i c a l c o v e r a g e of t h e a t m o s p h e r e results f r o m five or six c h a n n e l s p l a c e d in t h e w4 b a n d of m e t h a n e a t 7.5/zm, b u t e n e r g y c o n s t r a i n t s r e n d e r t h i s e x p e r i m e n t m a r g i n a l a t S a t u r n a n d useless a t Uranus and Neptune. For the outermost planets, t h e b e s t e x p e r i m e n t is t h r e e of four c h a n n e l s l o c a t e d in t h e l o n g - w a v e l e n g t h h a l f of t h e p r e s s u r e - i n d u c e d S(0) line of h y d r o g e n , in t h e r a n g e 25-40/~m w i t h w h i c h a l i m i t e d v e r t i c a l r a n g e of a b o u t two scale h e i g h t s c a n b e covered. Some r e s u l t s of i n v e r s i o n of s y n t h e t i c d a t a are p r e s e n t e d in e a c h case, a n d t h e likely effect o f clouds o n t h e m e a s u r e m e n t s is discussed. TRAFTO~, L., 1972. O n t h e possible d e t e c t i o n of H 2 in T i t a n ' s a t m o s p h e r e . Ap . J, 175, 285-293. W e a k a b s o r p t i o n f e a t u r e s in T i t a n ' s s p e c t r u m a t t h e w a v e l e n g t h s of t h e 3 - 0 S(1) H2 q u a d r u p o l e line a n d , w i t h less c e r t a i n t y , t h e S(0) line of t h e s a m e b a n d were d e t e c t e d . T h e p r o b a b l e r e a l i t y of t h e s e f e a t u r e s in t e r m s of a s t a t i s t i c a l a n a l y s i s of t h e p h o t o m e t r i c d a t a a n d p r e s e n t e v i d e n c e t h a t t h e y are n o t s c a t t e r e d f r o m S a t u r n b y t h e s k y or t h e telescope are discussed. T h e a b u n d a n c e i m p l i e d if t h i s a b s o r p t i o n arises f r o m H2 are e s t i m a t e d a n d t h e i m p l i c a t i o n s t h i s h a s for escape a n d o u t g a s s i n g r a t e s are discussed. TRAFTON, L., 1972. T h e b u l k c o m p o s i t i o n of T i t a n ' s a t m o s p h e r e . Ap . J. 175, 295-306. T h e m e t h a n e b a n d s in T i t a n ' s s p e c t r u m are s h o w n to be saturated and that, consequently, either t h e m e t h a n e a b u n d a n c e is n e a r l y a n o r d e r o f m a g n i t u d e g r e a t e r t h a n is generally b e l i e v e d or else m e t h a n e is a m i n o r c o n s t i t u e n t in t h i s a t m o s p h e r e . C o n s i d e r a t i o n of t h e p h y s i c a l c o n s t r a i n t s for T i t a n ' s a t m o s p h e r e leads to a m o d e l w h i c h describes t h e b u l k c o m p o s i t i o n in terms of observable parameters. Intermediater e s o l u t i o n p h o t o m e t r i c scans of b o t h S a t u r n a n d T i t a n , i n c l u d i n g scans of t h e Q - b r a n c h of T i t a n ' s 3v a m e t h a n e b a n d , c o n s t r a i n t h e s e p a r a m e t e r s in s u c h a w a y t h a t t h e m o d e l i n d i c a t e s t h e p r e s e n c e of a n o t h e r i m p o r t a n t a t m o s p h e r i c gas. T h e s i m p l e s t i n t e r p r e t a t i o n s of t h e p u b l i s h e d o b s e r v a t i o n s are n o t all comp a t i b l e ; f u r t h e r progress in d e t e r m i n i n g t h e c o m p o s i t i o n a n d s t a t e of T i t a n ' s a t m o s p h e r e requires additional observations to eliminate the present ambiguities. TaVBITSYN, V. P., 1972. A d i a b a t i c m o d e l for J u p i t e r . Soy. A s t r o n . - - A J 16, 342-347. A d i a b a t i c

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AFCRL BIBLIOGRAFI-IY--3RD QUARTER 1 9 7 2

c u r v e s are d e r i v e d for gaseous-liquid h y d r o g e n a n d h e l i u m . T h e t e m p e r a t u r e d i s t r i b u t i o n in a n a d i a b a t i c m o d e l of J u p i t e r is calculated. This m o d e l implies t e m p e r a t u r e s of a b o u t 5 × 104°K a t t h e c e n t e r of t h e p l a n e t . VASIL'EV, V. P., VOLOVIK, V. D., AND ZALYUBOVSKH, I. I., 1972. E x t e n s i v e air showers o n J u p i t e r , a n d its sporadic d e c a m e t e r radio emission. Sov. A s t r o n . - - A J 16, 337-341. A n e w e x p l a n a t i o n is p r o p o s e d for t h e origin of t h e s p a r a d i c r a d i o emission of J u p i t e r , c o n s i s t e n t w i t h t h e m a i n o b s e r v a t i o n a l e v i d e n c e o n decam e t e r b u r s t s . T h e source of t h e radio b u r s t s a t all t h e frequencies o b s e r v e d is c o n s i d e r e d to be t h e c o h e r e n t r a d i o emission of e x t e n s i v e air showers, amplified in t h e p l a n e t ' s ionosphere. T h e r a d i a t i o n is intensified b y a m a s e r m e c h a n ism b a s e d o n s p i n - e l e c t r o n t r a n s i t i o n s . T h e c o n d i t i o n s g i v i n g rise to t h i s i n t e n s i f i c a t i o n are p r o d u c e d b y a r e o r i e n t a t i o n of e l e c t r o n m a g n e t i c m o m e n t s d u e t o c h a n g e s in t h e d i r e c t i o n of t h e m a g n e t i c field in t h e ionosphere. These c h a n g e s are associated w i t h t h e m o t i o n t h r o u g h t h e i o n o s p h e r e of t h e base of a m a g n e t i c field t u b e frozen i n t o t h e satellite Io, a n d also w i t h t h e r e o r g a n i z a t i o n of t h e m a g n e t i c field as t h e position of t h e n o r t h m a g n e t i c pole varies because of t h e r o t a t i o n of J u p i t e r . PLANETS---MARS ALESHIN, V. I., AND SHCtIUKO, O. B., 1972. N a t u r e of t h e p o l a r c a p s on Mars. Sov, A s t r o n . - A J 16, 331-336. T h e h y p o t h e s i s o f a p u r e CO2 c o m p o s i t i o n for t h e p o l a r caps of Mars c a n n o t e x p l a i n t h e o b s e r v e d t i m e of a p p e a r a n c e of these formations at any areographic latitude. B u t t h e empirical d a t a c a n r e a d i l y b e interp r e t e d b y a s s u m i n g t h a t t h e caps a p p e a r w h e n w a t e r v a p o r begins to c o n d e n s e o n t h e g r o u n d surface, a n d t h a t w a t e r v a p o r c o n t i n u e s t o freeze o u t o n t o p of a l a y e r of CO2 snow (dry ice), t h e m a i n c o n s t i t u e n t of t h e caps. T h e CO2 snow p r o t e c t s t h e H 2 0 snow f r o m e v a p o r a t i n g in t h e d a y t i m e . H e n c e H 2 0 c o n t i n u e s to f o r m u n t i l t h e CO2 h a s c o m p l e t e l y v a n i s h e d b y l a t e spring. As t h e a l t i t u d e of t h e s u n increases, a n H 2 0 snow layer, responsible for t h e optical p r o p e r t i e s of t h e caps, will f o r m o n t h e dry-ice layer. M o i s t e n i n g of t h e g r o u n d w o u l d e x p l a i n t h e " d a r k r i m . " L i q u i d H 2 0 c o u l d develop w h e n t h e e n t i r e m a s s of H 2 0 snow t h a t h a s c o n d e n s e d d u r i n g t h e w i n t e r m e l t s in a few days, r e s u l t i n g in a rise in h u m i d i t y n e a r t h e edge of t h e m e l t i n g p o l a r cap. BARKER, E. S., 1972. D e t e c t i o n of m o l e c u l a r o x y g e n in t h e M a r t i a n a t m o s p h e r e . Nature 238, 447-448. Molecular o x y g e n (O2) h a s b e e n

d e t e c t e d spectroscopically in t h e a t m o s p h e r e of Mars, u s i n g lines in t h e 7 6 2 0 A A - b a n d . T h e a v e r a g e o b s e r v e d 02 a b u n d a n c e is 9.5 ± 0 . 6 c m atmosphere. BLUMSACK, S. L., AND GIERASCH, P. J., 1972. M a r s : T h e effects of t o p o g r a p h y o n b a r o c l i n i e i n s t a b i l i t y . J . Atmos. Sci. 29, 1081-1089. T h e effects of a sloping lower b o u n d a r y o n t h e q u a s i g e o s t r o p h i c baroclinic i n s t a b i l i t y m o d e l of E a d y are considered. A l t h o u g h t h e a n a l y t i c a l m o d e l is too simplified for d i r e c t a p p l i c a t i o n to M a r t i a n c o n d i t i o n s , t h e results s h o u l d b e useful in t h e i n t e r p r e t a t i o n of o b s e r v a t i o n s a n d n u m e r i c a l e x p e r i m e n t s . F o r slope o r i e n t a t i o n s of m o s t i n t e r e s t o n Mars, t h e w a v e l e n g t h , g r o w t h r a t e a n d h e a t fluxes associated w i t h t h e m o s t u n s t a b l e w a v e s are decreased. As a result, t h e r a d i a t i v e - d y n a m i c a l e q u i l i b r i u m s t a t e is closer to r a d i a t i v e e q u i l i b r i u m t h a n one w o u l d calc u l a t e for a m o d e l w i t h a h o r i z o n t a l lower boundary. CARLETON, N. P., AND TRAUB, W. A., 1972, D e t e c t i o n of m o l e c u l a r o x y g e n o n Mars. Science 177, 988-992. Molecular o x y g e n was d e t e c t e d in m a r t i a n s p e c t r a n e a r 7635 a n g s t r o m s a n d its abundance measured both during and after t h e 1971 d u s t s t o r m . I t s c o l u m n a b u n d a n c e in t h e clear m a r t i a n a t m o s p h e r e is a b o u t 10.4 ± 1.0 c e n t i m e t e r s a m a g a t , g i v i n g a m i x i n g r a t i o of m o l e c u l a r o x y g e n t o c a r b o n d i o x i d e o f l . 3 × 10 -3. T h e m i x i n g r a t i o of m o l e c u l a r o x y g e n to c a r b o n m o n o x i d e ( 1 . 4 ± 0 . 3 ) is q u i t e different from t h e v a l u e of 0.5 t h a t w o u l d r e s u l t f r o m t h e p h o t o l y s i s of a p u r e c a r b o n dioxide a t m o s p h e r e , w h i c h i n d i c a t e s t h a t t h e r e is or was a n e t source of o x y g e n r e l a t i v e to c a r b o n ( p r o b a b l y w a t e r ) in t h e m a r t i a n a t m o s p h e r e . CODE, A. D., AND SAVAGE, B. D., 1972. O r b i t i n g a s t r o n o m i c a l o b s e r v a t o r y : R e v i e w of scientific results. Science 177, 213-221. See Comets. GREELEY, R., AND HYDE, J . H . , 1972. L a v a t u b e s of t h e Cave B a s a l t , M o u n t St. Helens, W a s h i n g t o n . Geol. Soc. Amer. Bull. 83, 2 3 9 7 2418. See M o o n - - S u r f a c e F e a t u r e s . KOPAL, Z., 1972. Cosmic influences of t h e early h i s t o r y o f t h e l u n a r surface. The M o o n 5, 200205. See M o o n - - S u r f a c e F e a t u r e s . KROTIKOV, V. D., AND SHCHUKO, 0 . B., 1972. T e m p e r a t u r e c o n d i t i o n s in t h e t o p surface l a y e r of Mars d u r i n g t h e 1971 opposition. Sov. Astron. - - - A J 16, 129-131. A t h e o r e t i c a l a n a l y s i s is m a d e of t h e t e m p e r a t u r e c o n d i t i o n s to b e e x p e c t e d in t h e surface l a y e r of Mars d u r i n g t h e 1971 opposition. I s o t h e r m c h a r t s are p r e p a r e d for t h e s u n l i t surface. T h e d i u r n a l t e m p e r a t u r e v a r i a t i o n s a t different a r e o g r a p h i e l a t i t u d e s are r e p r e s e n t e d b y a F o u r i e r series. T h e e a s t - w e s t

PLANETS--NEPTUNE a s y m m e t r y of t h e surface h e a t i n g m a y conv e n i e n t l y b e u s e d to e s t i m a t e t h e t h e r m a l p a r a m e t e r ~/ = (kpc) -1/2. MASU~SKY, H . , ARTHUR, D., BATSON, R., BORGESON, W., BRIGGS, G., CARR, M., CHANDEYSSON, P., CUTTS, J., DAVIES, M., DE-

VAUCOULEURS, C., HARTMANN,W., LEDERBERG, J . , LEIGHTON, t{., LEOVY, C., LEVINTItAL, E., MCCAULEY, J . , MILTON, D., MURRAY, B., POLLACK, J., SAGAN, C., SHARP, R., SHIPLEy, E., SMITH, B.~ SODERBLOM, L., VEVERKA, J., WILDEY, R., WILttELMS, D., AND YOUNG, A., 1972. T h e N e w M a r i n e r 9 m a p of Mars. S k y and Telescope 44, 77-82 + f o l d - o u t m a p . T h e Mars m a p is p r e s e n t e d as a five page fold out. T h e t e x t reviews t h e h i s t o r y of M a r t i a n m a p p i n g a n d describes h o w t h e n e w m a p was p r o d u c e d . P h o t o g r a p h s of t y p e s of M a r t i a n t e r r a i n are presented. McELROY, M. B., AND DONAHUE, W. M., 1972. S t a b i l i t y of t h e M a r t i a n a t m o s p h e r e . Science 177, 986-988. A d e t a i l e d c h e m i c a l d y n a m i c m o d e l is p r e s e n t e d for a m o i s t m a r t i a n a t m o s phere. R e c o m b i n a t i o n of c a r b o n dioxide is c a t a l y z e d b y t r a c e a m o u n t s of w a t e r . T h e a b u n d a n c e s of c a r b o n m o n o x i d e a n d m o l e c u l a r o x y g e n s h o u l d v a r y in response to c h a n g e s in atmospheric water and atmospheric mixing.

OBERBECK, V. I~., AOYAGI, M., AND MURRAY, J . B., 1972. C i r c u l a r i t y of M a r t i a n craters. Mod. Geol. 3, 195-199. A modified m e t h o d of calculating crater circularity based on the a v e r a g e d e v i a t i o n of c r a t e r r a d i u s f r o m m e a n r a d i u s is p r e s e n t e d a n d used to c a l c u l a t e c i r c u l a r i t y of M a r t i a n craters. C a l c u l a t i o n of t h e c i r c u l a r i t y indices of o v e r 200 M a r t i a n c r a t e r s yields v a l u e s similar to c i r c u l a r i t y indices of t e r r e s t r i a l m e t e o r i t e c r a t e r s a n d different f r o m indices of t e r r e s t r i a l calderas. SAGAN, C., AND MULLEN, G., 1972. E a r t h a n d M a r s : E v o l u t i o n of a t m o s p h e r e s a n d surface t e m p e r a t u r e s . Science 177, 52-56. Solar e v o l u t i o n implies, for c o n t e m p o r a r y a l b e d o s a n d a t m o s p h e r i c c o m p o s i t i o n , global m e a n t e m p e r a t u r e s below t h e freezing p o i n t of s e a w a t e r less t h a n 2.3 a e o n s ago, c o n t r a r y to geologic a n d paleontological evidence. A m m o n i a m i x i n g r a t i o s of t h e o r d e r of a few p a r t s p e r million in t h e m i d d l e P r e c a m b r i a n a t m o s p h e r e resolve t h i s a n d o t h e r p r o b l e m s . Possible t e m p e r a t u r e e v o l u t i o n a r y t r a c k s for E a r t h a n d Mars are described. A r u n a w a y g r e e n h o u s e effect will o c c u r o n E a r t h a b o u t 4.5 a e o n s f r o m now, w h e n c l e m e n t cond i t i o n s will p r e v a i l o n Mars. SMITH, t I . T. U., 1972. A e o l i a n d e p o s i t i o n in M a r t i a n craters. Nature 238, 72-74. T h e Merid i a n i Sinus region c o m p r i s e s a n e l o n g a t e d a r e a of d a r k t e r r a i n enclosed b y l i g h t or " d e s e r t "

117

terrain. Within the dark terrain, many craters in t h e general size r a n g e of 25 to 6 0 k m d i a m e t e r d i s p l a y c o n s p i c u o u s l y a s y m m e t r i c albedo. L i g h t areas c o v e r f r o m a b o u t 2 0 - 6 0 % of t h e floors of c r a t e r s in w h i c h a s y m m e t r y is e v i d e n t . T h e cross profile of t h e c r a t e r a p p e a r s to b e a s y m m e t r i c , w i t h t h e l i g h t a n d d a r k areas r e p r e s e n t i n g two d i s t i n c t l y different t y p e s of surface, s e p a r a t e d b y a t o p o g r a p h i c d i s c o n t i n u i t y . Such a d e p o s i t is b e s t e x p l a i n e d as h a v i n g b e e n s u p p l i e d f r o m w i n d a c t i o n b y s a l t a t i o n a n d creep, l e a d i n g to selective a c c u m u l a t i o n of b l o w n s a n d u n d e r t h e c o n t r o l of t o p o g r a p h i c obstacles or t r a p s . I f t h e i n t e r p r e t a t i o n is correct, it i n d i c a t e s t h e prev a i l i n g w i n d d i r e c t i o n ; t h e occurrence of l i g h t areas o n n o r t h e r n sides of c r a t e r s suggests s a n d t r a n s p o r t f r o m t h a t direction, t o f o r m falling d u n e s w h e r e r e a c h i n g c r a t e r edges, a n d t h e t e r r e s t r i a l a n a l o g u e s are c o n s i s t e n t w i t h t h i s interpretation. STRICKLAND, D. J., THOMAS, G. E., AND SPARKS, P. R., 1972. M a r i n e r 6 a n d 7 u l t r a v i o l e t s p e c t r o m e t e r e x p e r i m e n t : A n a l y s i s of t h e O I 1304- a n d 1356-A emissions. J. Geophys. Res. 77, 4052-4068. A n analysis of t h e 0 I 1304- a n d 1356-A d a t a f r o m M a r i n e r 6 a n d 7 is p r e s e n t e d , a n d t h e a t o m i c o x y g e n c o n c e n t r a t i o n of t h e M a r t i a n a t m o s p h e r e is e s t i m a t e d . D e r i v e d v a l u e s of t h e p a r a m e t e r s d e s c r i b i n g t h e sources of e x c i t a t i o n differ c o n s i d e r a b l y f r o m p r e v i o u s e s t i m a t e s . A d e t a i l e d s t a t i s t i c a l t r e a t m e n t is used in t h e analysis. A t a n exospheric t e m p e r a t u r e of 350°K t h e a t o m i c o x y g e n c o n c e n t r a t i o n a t 1 3 5 k m is e s t i m a t e d to b e b e t w e e n 0.5 a n d 1%. T h e likely source of t h e 1304-A i n t e n s i t y is r e s o n a n c e s c a t t e r i n g of solar 1304-A p h o t o n s . F o r t h e 1356-A emission, t h e likely source is p h o t o d i s s o c i a t i o n of CO2. T h e r e is a n i n d i c a t i o n of a d i u r n a l v a r i a t i o n of t h e M a r t i a n u p p e r atmosphere. WELLS, R. A., 1972. M a r s : Are o b s e r v e d w h i t e clouds c o m p o s e d of II207 .Nature 238, 324-326. A l t h o u g h M a r t i a n w h i t e cloud frequencies t e n d t o follow t h e d i s t r i b u t i o n of H 2 0 b o t h seasonally and latitudinally on the planet, which strongly suggests t h a t m o s t w h i t e clouds are f o r m e d f r o m w a t e r v a p o u r , e v i d e n c e for t h e c o m p o s i t i o n of t h e b l u e clouds is still lacking.

PLANETS--NEPTUNE CHAPRONT, J . , AND SIMON, J . L., 1972. Secular v a r i a t i o n s of t h e first order, for t h e four m a j o r p l a n e t s . C o m p a r i s o n w i t h Le V e r r i e r a n d Gaillot. Astron. Astrophys. 19, 231-234. See Planets---Jupiter. CODE, A. D., AND SAVAGE, B. D., 1972.

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ArCRL B I B L I O G R A P H Y - - 3 R D QUARTER 1 9 7 2

O r i b i t i n g a s t r o n o m i c a l o b s e r v a t o r y : R e v i e w of scientific results. Science 177, 213-221. See Comets. TAYLOR, F. W., 1972. T e m p e r a t u r e s o u n d i n g e x p e r i m e n t s for t h e J o v i a n p l a n e t s . J. Atmos. Sci. 29, 950-958. See P l a n e t s - - J u p i t e r .

PLANETS--~PLUTO BARBIERI, C., CAPACCIOLI, M., GANZ, R., AND PINTO, G., 1972. A c c u r a t e positions of t h e p l a n e t P l u t o in t h e y e a r s 1969-1970. Astron. J. 77, 521-522. S i x t e e n positions of t h e p l a n e t P l u t o i n t h e y e a r s 1969 1970 are g i v e n r e f e r r e d t o A G K 3 stars. T h e positions, w h i c h h a v e b e e n m e a s u r e d on p l a t e s t a k e n w i t h t h e 6 7 - 9 2 - c m Asiago S e h m i d t telescope, h a v e a s t a n d a r d e r r o r of 0":34 in R.A. a n d 0'.'26 in Dee.

PLANETS--SATURN BOBROV, M. S., 1972. T h i c k n e s s of S a t u r n ' s rings f r o m o b s e r v a t i o n s in 1966. Sov. Astron.-A J 16, 348-354. A discussion is g i v e n of t h e m e t h o d s a n d results of e s t i m a t i n g t h e t h i c k n e s s Z0 of S a t u r n ' s rings f r o m p h o t o m e t r y of t h e rings o b s e r v e d edge-on. T h e o b s e r v a t i o n a l difficulties a n d p r o c e d u r e s for o v e r c o m i n g t h e m are considered. T h e p h o t o m e t r i c series o b t a i n e d b y K i l a d z e a n d b y Focus a n d Dollfus in 1966 are a n a l y z e d . B o t h series are s a t i s f a c t o r i l y repr e s e n t e d b y a p l a n e - p a r a l l e l m o d e l of t h e rings ; t h e corrections to t h e e p h e m e r i s epochs of t h e e a r t h ' s passage t h r o u g h t h e ring p l a n e are in good a g r e e m e n t for t h e two series, b u t t h e e s t i m a t e s of Z o (reduced t o t h e s a m e b r i g h t n e s s for t h e edge of t h e rings) differ b y a f a c t o r of 5 (0.57 a n d 2.8kin, respectively), m o r e t h a n t h e errors of m e a s u r e m e n t . Possible sources of t h e d i s p a r i t y are discussed. CHAPRONT, J., A:ND SIMON, J . L., 1972. Secular v a r i a t i o n s of t h e first order, for t h e four m a j o r p l a n e t s . C o m p a r i s o n w i t h Le V e r r i e r a n d Gaillot. Astron. Astrophys. 19, 231-234. See Planets~upiter. CODE, A. D., A~D SAVAGE, B. D., 1972. O r b i t i n g a s t r o n o m i c a l o b s e r v a t o r y : R e v i e w of scientific results. Science 177, 213-221. See Comets. ]~IAMEEN-ANTTILA, K . A., AND PYYKKO, S., 1972. P h o t o m e t r i c b e h a v i o u r of S a t u r n ' s rings as a f u n c t i o n of t h e S a t u r n o c e n t r i c l a t i t u d e s of t h e E a r t h a n d t h e Sun. Astron. Astrophys. 19, 235-247. T h e surface b r i g h t n e s s of S a t u r n ' s rings A a n d B are d e t e r m i n e d for a c o n s t a n t p h a s e 3 .°5 as a f u n c t i o n of t h e solar a n d t e r r e s t r i a l e l e v a t i o n

angles. T h e l i g h t c u r v e for r i n g A follows t h e L o m m e l - S e e l i g e r law c o r r e c t e d for a m i n o r effect p r o d u c e d b y m u l t i p l e s c a t t e r i n g . T h e i n t e n s i t y of r i n g B increases w i t h t h e e l e v a t i o n angles. M u l t i p l e s c a t t e r i n g does n o t e x p l a i n t h i s p h e n o m e n o n b u t s t r a t i f i c a t i o n does. A g r e e m e n t w i t h o b s e r v a t i o n s is a c h i e v e d if ring B consists of particles i d e n t i c a l w i t h t h o s e in ring A while also possessing a l o n g its e q u a t o r i a l p l a n e a n a r r o w l a y e r of m u c h b r i g h t e r particles. A t h e o r e t i c a l e x p l a n a t i o n for s t r a t i f i c a t i o n a n d for t h e difference in a l b e d o s is g i v e n in t e r m s of size differences. SINCLAIR, A. T., 1972. Oil t h e origin of t h e c o m m e n s u r a b i l i t i e s a m o n g s t t h e satellites of S a t u r n . M . N. R. A. S. 160, 169-187. T h e hypothesis that the commensurabilities amongst t h e satellites of S a t u r n are d u e to t h e a c t i o n o f t i d a l forces is e x a m i n e d . I t is s h o w n t h a t t h i s hypothesis provides a satisfactory explanation of t h e origin of t h e c o m m e n s u r a b i l i t i e s b e t w e e n Mimas and Tethys, and between Enceladus and Dione. T h e origin of t h e c o m m e n s u r a b i l i t y b e t w e e n T i t a n a n d H y p e r i o n c a n n o t b e exp l a i n e d in t h i s way, b u t it is possibly t h e r e s u l t of a close a p p r o a c h b e t w e e n t h e s e satellites. TAYLOR, F. V¢'., 1972. T e m p e r a t u r e s o u n d i n g e x p e r i m e n t s for t h e J o v i a n p l a n e t s . J. Atmos. Sci. 29, 950-958. See P l a n e t s - - J u p i t e r . TRULSEN, J., 1972. On t h e rings of S a t u r n . Astrophys. Space Sci. 17, 330-337. R e s u l t s f r o m n u m e r i c a l s i m u l a t i o n s of j e t s t r e a m s are u s e d t o discuss c e r t a i n aspects of t h e d y n a m i c s of t h e rings of S a t u r n . T h e p r o b a b l e v e l o c i t y distrib u t i o n inside t h e ring s y s t e m is s t r o n g l y nonMaxwellian. F o r t h e rings to f o r m a n d r e m a i n a m i n i m a l degree of i n e l a s t i c i t y is r e q u i r e d . T h e e n e r g y c o n s u m p t i o n decreases r a p i d l y w i t h d e c r e a s i n g t h i c k n e s s of t h e rings. As we e x p e c t t h e degree of i n e l a s t i c i t y to decrease for v e r y small i m p a c t velocities, a m i n i m a l t h i c k n e s s s h o u l d be reached, s o m e w h a t lower t h a n t h e o b s e r v e d value.

PLANETS~URANUS CHAERONT, J . , AI~/D SIMON, J . L., 1972. Secular v a r i a t i o n s of t h e first order, for t h e four m a j o r p l a n e t s . C o m p a r i s o n w i t h Le Verrier a n d Gaillot. Astron. Astrophys. 19, 231-234. See Planets-~Jupiter. CODE, A. D., AND SAVAGE, B. D., 1972. O r b i t i n g a s t r o n o m i c a l o b s e r v a t o r y : R e v i e w of scientific results. Science 177, 213-221. See Comets. LUTZ, B. L., AND RAMSAY, D. A., 1972. N e w o b s e r v a t i o n s o n t h e K u i p e r b a n d s of U r a n u s .

PLANETS--VENUS

Ap. J. 176, 521-524. T h e 7 5 0 0 A K u i p e r b a n d s of U r a n u s h a v e b e e n r e p h o t o g r a p h e d a t 1 0 A m m -1 dispersion u t i l i z i n g a n e l e c t r o s t a t i c i m a g e intensifier. C o m p a r i s o n of t h e s e b a n d s w i t h n e w l o n g - p a t h l a b o r a t o r y s p e c t r a of m e t h a n e (up to 8 . 4 5 k m - a t m ) confirms t h a t it is responsible for t h e b a n d s . T w e n t y n e w U r a n i u m b a n d s are r e p o r t e d , of w h i c h a t least eight, a n d possibly all, are d u e t o m e t h a n e . E q u i v a l e n t w i d t h s of some of t h e p l a n e t a r y f e a t u r e s are p r e s e n t e d for c o m p a r i s o n w i t h f u t u r e l a b o r a t o r y s p e c t r a . SINTON, W. M., 1972. L i m b a n d p o l a r b r i g h t e n ing of U r a n u s a t 8870/~. Ap. J. 176, L 1 3 1 - L 1 3 3 . P h o t o g r a p h s of U r a n u s in t h e 8870/~ b a n d of methane exhibit limb brightening and brightening a t t h e s o u t h pole. T h e p o l a r b r i g h t e n i n g is e x p l a i n e d b y a n u p p e r a t m o s p h e r i c h a z e in a d d i t i o n to R a y l e i g h s c a t t e r i n g b y t h e u p p e r a t m o s p h e r e . A n e s t i m a t e of t h e g e o m e t r i c a l b e d o a t t h i s w a v e l e n g t h yields a v a l u e n e a r 0.01. TAYLOR, F. W., 1972. T e m p e r a t u r e s o u n d i n g e x p e r i m e n t s for t h e J o v i a n p l a n e t s . J. Atmos. Sei. 29, 950-958. See P l a n e t s - - J u p i t e r .

119

M e a s u r e m e n t s of t h e visibilities w i t h a n a c c u r a c y o n t h e o r d e r of 0.001 of t h e t o t a l p l a n e t a r y flux ( 1 m v i s ) are n e c e s s a r y t o i m p r o v e e s t i m a t e s of t h e planetary parameters. For ll.l-cm wavelength a n d t h e r e f e r e n c e - m o d e l p a r a m e t e r s , surfacet e m p e r a t u r e v a r i a t i o n s w i t h l a t i t u d e a n d longit u d e cause c h a n g e s i n t h e visibilities of a b o u t 1 m v i s for each p e r c e n t t h e m a x i m m n t e m p e r a t u r e varies from the mean. PRINN, R. G., 1972. Venus atmosphere: Structure and stability of the CIOO radical. J. Atmos. Sci. 29, 1004-1007. The CIOO radical has been suggested as an important intermediate in a Cl atom catalyzed combination of CO and 02 enabling conservation of the observed lou T mixing ratios for CO and 02 in the predominantly C02 Venusiau atmosphere. The author reviews evidence concerning the existence, structure and stability of this radical. From theoretical considerations he concludes that the decomposition rate for CIOO in conditions appropriate to the Venus atmosphere is pressure-dependent' with a second-order rate constant given approximately by 5.2 × 1 0 - 9 e x p ( - 4 0 4 0 / T ) [cm a see-l].

PLANETS~VENUS BARTLETT, J . W., AND HUNT, G. E., 1972. V e n u s cloud cover. Nature 238, 11-12. G o o d y a n d R o b i n s o n h a v e s u g g e s t e d a general u p w a r d m o t i o n in t h e V e n u s a t m o s p h e r e w h i c h is c o m p e n s a t e d b y a small a r e a of r a p i d l y descending m o t i o n o n t h e d a r k side of t h e p l a n e t . A r g u m e n t s are p r e s e n t e d w h i c h i n d i c a t e t h a t t h e r e n e e d b e no cloud free region o n V e n u s . CODE, A. D., AND SAVAGE, n . D., 1972. O r b i t i n g a s t r o n o m i c a l o b s e r v a t o r y : R e v i e w of scientific results. Science 177, 213-221. See Comets. GALE, W. i . , AND SINCLAIR, A. C. E., 1972. H o w to m e a s u r e surface a n d a t m o s p h e r i c conditions on Venus by microwave interferem e t r y . Ap. J. 175, 535-554. P r e d i c t i o n s of t h e polarized a n d u n p o l a r i z e d i n t e r f e r o m e t r i c visibilities of V e n u s are m a d e for w a v e l e n g t h s f r o m 3 c m to 100cm. T h e basis for t h e p r e d i c t i o n s is a m u l t i p a r a m e t e r p l a n e t a r y m o d e l of b r i g h t n e s s temperature. Experimental inferferometric r e s u l t s a t l l . I c m are r e p o r t e d i n a c o m p a n i o n p a p e r , a n d h e l p e d to select t h e p a r a m e t e r v a l u e s o f t h e reference model. S e n s i t i v i t y calculations, varying the planetary parameters from their reference m o d e l v a l u e s were m a d e . S h o r t i n t e r f e r o m e t e r baselines, a t w h i c h t h e u n p o l a r i z e d v i s i b i l i t y is n e a r its first null, yield optimum parameter sensitivities; thus extensive high-resolution mapping is unnecessary.

T h i s r a t e is p r o b a b l y sufficiently slow to e n a b l e t h e o x i d a t i o n of CO b y CIOO to successfully c o m p e t e w i t h ClOO d e c o m p o s i t i e n , a t least t o the extent required to maintain the observed c o m p o s i t i o n of t h e V e n u s a t m o s p h e r e . SINCLAIR, A. C. E., BASART, J. P., BUHL, D., AND GALE, W. A., 1972. P r e c i s i o n i n t e r f e r o m e t r i c o b s e r v a t i o n s of V e n u s a t l l . l - c e n t i m e t e r w a v e l e n g t h . Ap. J. 175, 555-572. P r e c i s i o n m e a s u r e m e n t s were m a d e of V e n u s ' s i n t e r f e r o m e t r i c v i s i b i l i t y for b o t h t h e t o t a l a n d t h e p o l a r i z e d radiation at ll.l-cm wavelength. The observations showed that at this wavelength the brightness of t h e p l a n e t ' s disk h a s s u b s t a n t i a l l y c i r c u l a r s y m m e t r y . B y a n a l y s i s of t h e d a t a a c c o r d i n g to a simple p l a n e t a r y m o d e l t h e a u t h o r s d e d u c e d v a l u e s of t w o p l a n e t a r y p a r a m e t e r s , o b t a i n i n g 3.90 ± 0.15 for t h e dielectric c o n s t a n t of t h e surface a n d 0 . 6 5 % ± 0 . 1 2 % for t h e w a t e r c o n t e n t of V e n u s ' s a t m o s p h e r e , w h e r e t h e q u o t e d u n c e r t a i n t i e s reflect o n l y e x p e r i m e n t a l error. T h e a u t h o r s discuss t h e effects of errors i n a s s u m p t i o n s for t h e m o d e l parameters. YOUNG, L. D. G., AN]) YOUNG, A. T., 1972. O n t h e t e m p e r a t u r e d i s t r i b u t i o n in a p l a n e t a r y a t m o s p h e r e . Ap. J. 176, 533-554. A s e n s i t i v e m e t h o d for e s t i m a t i n g t h e r a n g e of t e m p e r a t u r e i n t h e p a r t of t h e a t m o s p h e r e w h e r e s p e c t r a l lines are f o r m e d , f r o m o b s e r v a t i o n s m a d e i n reflected s u n l i g h t is p r e s e n t e d . T h i s m e t h o d is

120

AFCRL BIBLIOGRAPFIY--3RD QUARTER 1972

a p p l i e d to t h e b e s t available spectroscopic o b s e r v a t i o n s o f V e n u s m a d e in t h e 78202~ COz b a n d . S t a t i s t i c a l t e s t s suggest t h a t we are n o t seeing a n i s o t h e r m a l layer, b a s e d on t h e s e d a t a . H o w e v e r , a 100°K t e m p e r a t u r e s p r e a d is n e a r t h e limit o f d e t e c t i o n w i t h p r e s e n t o b s e r v a t i o n a l techniques. TEKTITES BOU~KA, V., AND R e s T , R., 1972. D o u b l e m o l d a v i t e s in S o u t h e r n B o h e m i a . Science 177, 519-520. Two n o t e w o r t h y finds o f m o l d a v i t e s were m a d e in s o u t h e r n B o h e m i a . I n b o t h cases t w o m o l d a v i t e s are t h r u s t into each other. The collision e v i d e n t l y t o o k place d u r i n g t h e flight o f a n i n h o m o g e n e o u s s w a r m of m o l d a v i t e s , still plastic b u t a l r e a d y d i s p l a y i n g a l m o s t definite a e r o d y n a m i c shapes. I t is t h e first t i m e such m o l d a v i t e s h a v e been e n c o u n t e r e d , a n d t h e a u t h o r s p r o p o s e to d e s i g n a t e t h e m as double moldavites. FAUL, H., AND WAGNER, G. A., 1972. Vagab o n d t e k t i t e s . E a r t h Planet. Sci. Lett. 14, 357-359. U n d e r t h e title " A C u b a n T e k t i t e " Garlick et al. describe a t e k t i t e " f o u n d in a c a b i n e t once u s e d b y t h e late Dr. A P o l d e r v a a r t

a t C o l u m b i a U n i v e r s i t y " . The e x a c t location o f t h e find is n o t k n o w n a n d i n d i c a t i o n s are t h a t t h e o b j e c t was carried to Cuba b y m a n . GLASS, B. B., 1972. Crystalline inclusions in a M u o n g N o n g - t y p e i n d o c h i n i t e . E a r t h Planet. Sci. Lett. 16, 23-26. Zircon, c o r u n d m n , rutile, m o n a z i t e a n d q u a r t z (identified b y X r a y diffraction) h a v e b e e n r e c o v e r e d f r o m a M u o n g Nong-type indochinite. X ray asterism studies i n d i c a t e t h a t all o f t h e minerMs are s h o c k e d . T h e t e k t i t e glass s u r r o u n d i n g t h e rutile c r y s t a l s is a d a r k b r o w n color r a t h e r t h a n yellow-green like t h e rest o f t h e glass, i n d i c a t i n g t h a t t h e rutile was s t a r t i n g to m e l t . The c o r u n d u m a p p e a r s to be a d e c o m p o s i t i o n p r o d u c t of one o f t h e A12SiO 5 m i n e r a l s (kyanite, sillimanite or andalusite). T h e p r e s e n c e of a n Al2SiO s m i n e r a l s t r o n g l y suggests a m e t a m o r p h i c c o m p o n e n t in t h e t e k t i t e p a r e n t material. T h e p r e s e n c e o f zircon, rutile, m o n a z i t e , c h r o m i t e a n d q u a r t z as well as a n u n k n o w n a l u m i n u m silicate m i n e r a l in this a n d a n o t h e r M u o n g N o n g - t y p e t e k t i t e i n d i c a t e s t h a t t h e t e k t i t e s were p r o d u c e d f r o m a d e t r i t a l s e d i m e n t a r y m a t e r i a l . The p r e s e n c e o f t h e s e m i n e r a l s in M u o n g N o n g - t y p e t e k t i t e s seems t o s t r e n g t h e n t h e case for a t e r r e s t r i a l origin for t e k t i t e s .