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The distribution of trace elements in deep-sea sediments of the Atlantic Ocean
EARTH AND PLANETARY SCIENCE LETTERS 1 (1966) 161-168. NORTH-HOLLAND PUBL. COMP., AMSTERDAM
T H E D I S T R I B U T I O N OF T R A C E E L E M E N T S IN D E E P - S E A S E D I M E N T S O F T H E A T L A N T I C OCF..AN K a r l K. TUREKIAN and John IMBRIE Department of Geology, Yale University, New Haven, Connecticut and Department of Geology, Columbia University, New York, New York Received 26 May 1966
The distributions of barium, cobalt, copper, nickel, lead, chromium, manganese and tin have been determined in the tops of deep-sea cores from the Atlantic Ocean. The trace elements show no correlations with clay mineralogy or depth of water. The strongest correlations are. (1) among manganese, nickel and cobalt which can be related generally to areas of low clay accumulation rates hence possibly representing a fine grained pelagic component, and (2) the correlation of copper with calcium carbonate.
A s y s t e m a t i c study of the t r a c e - e l e m e n t c o m position of the tops of c o r e s r a i s e d by the Lamont Geological O b s e r v a t o r y in the Atlantic Ocean has been made u s i n g an e m i s s i o n s p e c t r o graphic technique [1]. The e l e m e n t s d e t e r m i n e d w e r e b a r i u m , copper, cobalt, nickel, lead, c h r o m i u m , m a n g a n e s e and tin. As the c o n c e n t r a t i o n of tin was below the l i m i t of detection (2 ppm) in many c o r e s it is not included in the s t a t i s t i c a l a n a l y s i s d e s c r i b e d below and the r e sults a r e not r e p o r t e d h e r e although it should be noted that a random d i s t r i b u t i o n p a t t e r n a p p e a r s to exist for this element. Figs. 1-5 show the d i s t r i b u t i o n s of cobalt, nickel, m a n g a n e s e , c h r o m i u m and copper, on a c a l c i u m c a r b o n a t e - f r e e b a s i s , in the tops of c o r e s r a i s e d i n the Atlantic Ocean. Maps of the d i s t r i b u t i o n s of b a r i u m and c a l c i u m c a r b o n a t e have been r e p o r t e d p r e v i o u s l y [2]. T h e r e was no s t r o n g p a t t e r n to the lead d i s t r i b u t i o n , hence a map of it is not included. It is evident that cobalt, nickel, m a n g a n e s e and copper a r e p r e s e n t in higher c o n c e n t r a t i o n s in the m i d - o c e a n i c a r e a r e l a t i v e to the deeper a r e a s between the MidAtlantic Ridge and the c o n t i n e n t a l m a r g i n s . This is also t r u e of b a r i u m , g e n e r a l l y , and also of c a l c i u m carbonate. B a r i u m is known to be a s s o ciated with high biological activity in some p a r t s of the oceans [2, 3] and the c a l c i u m carbonate d i s t r i b u t i o n r e f l e c t s both i n t e n s e productivity and the a s - y e t - u n r e s o l v e d effects of water depth. In o r d e r to pick out p o s s i b l e a s s o c i a t i o n s of the t r a c e e l e m e n t s with each other, w a t e r depth, c a l c i u m carbonate, and m i n e r a l o g y , a s t a t i s t i c a l a n a l y s i s of the data was made. The object of
such an a n a l y s i s is to quantify and evaluate c o r r e l a t i o n s which a r e intuitively apparent as well as to focus attention on c o r r e l a t i o n s not c l e a r l y d i s c e r n e d . With such c o r r e l a t i o n s or a b s e n c e s of c o r r e l a t i o n s we can then p r o c e e d to draw i n f e r ences about the p r o b a b l e p r o c e s s e s operative to explain the o b s e r v e d d i s t r i b u t i o n s and a s s o c i a tions. The m i n e r a l o g i c a l data a r e those of B i s caye [4]. The t r a c e e l e m e n t and carbonate d e t e r m i n a t i o n s were made on the same sample on which the clay m i n e r a l o g y was d e t e r m i n e d . Two sets of data were analyzed by a s t a t i s t i c a l technique (factor analysis) d e s c r i b e d p r e v i o u s l y [5]: (1) a set of 95 c o r e s for which b a r i u m data as well as the other data were available, totalling 16 v a r i a b l e s ; and (2) a set of 252 c o r e s including all the v a r i a b l e s except b a r i u m , totalling 15. A p r i n c i p a l components factor a n a l y s i s indicates that t h e r e a r e e s s e n t i a l l y nine independent sets of influences o p e r a t i n g in both sets of data. A v a r i m a x rotation p r o c e d u r e f u r t h e r i n d i c a t e s that the nine v a r i a b l e s displaying g r e a t e s t mutual independence a r e those listed f i r s t in each c l u s t e r in table 1. The tabled values a r e s t a n d a r d i z e d p a r t i a l l i n e a r r e g r e s s i o n coefficients r e l a t i n g the nine s e l e c t e d v a r i a b l e s to each of the sixteen. Only the most significant coefficient is r e c o r d e d for each v a r i a b l e . The r e s u l t s have been r e corded in table 1 to b r i n g out groupings of v a r i a b l e s with s i m i l a r dependencies. The clay m i n e r a l o g i c a l s t a t i s t i c a l data a r e in t h e m s e l v e s not p a r t i c u l a r l y i n f o r m a t i v e s i n c e the d i s t r i b u t i o n maps of the m i n e r a l s have been adequately i n t e r p r e t e d by B i s c a y e [4]. It is obvious f r o m the v i s u a l c o m p a r i s o n of the t r a c e -
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F i g . 1. M a p o f c o p p e r c o n c e n t r a t i o n in b o t t o m s e d i m e n t s o f t h e A t l a n t i c O c e a n calculated on a carbonate-free basis.
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DISTRIBUTION OF TRACE ELEMENTS
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DISTRIBUTION OF TRACE ELEMENTS IN DEEP-SEA SEDIMENTS Table 1 Results f r o m oblique projection m a t r i c e s (expressed as p a r t i a l l i n e a r r e g r e s s i o n coefficients) *. Variable No.
Including b a r i u m (sample = 95)
Excluding b a r i u m (sample = 252)
1
MANGAN NICKEL COBALT
1.000 0.914 0.764
NICKEL MANGAN COBALT
1.000 0.884 0.851
2
GIBILL KAOLIN
1.000 0.892
KAOLIN GIBILL CHLOR
1.000 0.670
-0.561
3
QUAILL AMPILL
1.000 0.860
QUAILL
1.000
4
MONT ILLITE CH LOR
1.00O -0.724 -0.794
MONT ILLITE
5
CALCAR COPPER
1.000 0.671
CALCAR COPPER
1.000 -0.827 1.000 0.846
6
LEAD
1.000
LEAD
1.000
7
CHROMI
1.000
CHROMI
1.000
8
DEPTH
1.000
DEPTH
1.000
9
BARIUM
1.000
AMPILL
1.000
a n d i s p r o b a b l y d u e to t h e d e p o s i t i o n of f i n e m a t e r i a l w i t h h i g h c o n c e n t r a t i o n s of t h e s e e l e m e n t s transported from the continents. A similar dist r i b u t i o n h~as b e e n o b s e r v e d f o r M n i n d e e p - s e a s e d i m e n t s of t h e P a c i f i c O c e a n b y S k o r n y a k o v a [7]. T h e c a l c i u m c a r b o n a t e i s a r e f l e c t i o n of t h e preserved productivity and although copper is n o t i n t h e l a t t i c e of t h e c a r b o n a t e t e s t s , i t i s i n s o m e way b i o l o g i c a l l y a s s o c i a t e d a n d e x t r a c t e d from sea water and preserved with the calcium c a r b o n a t e f r a c t i o n . R e v e l l e e t al. [8] a l s o n o t e d this qualitatively for Pacific sediments. The average trace-element concentration values for the Atlantic Ocean deep-sea clay sediments based on these results are compared with Wedepohl's averages for the Atlantic and Pacific in t a b l e 2. A d i s c u s s i o n of t h e b e a r i n g o f t h e s e r e sults on material balance type calculations in Table 2 T r a c e element concentrations in p a r t s p e r million. Present results Atlantic
* The code n a m e s for the v a r i a b l e s have the following meanings: MANGAN, NICKEL, COBALT, LEAD, BARIUM, CHROMI, COPPER stand for the concent r a t i o n s of the obvious t r a c e e l e m e n t s on a calcium c a r b o n a t e - f r e e b a s i s . KAOLIN, MONT, ILLITE, CHLOR r e p r e s e n t the percentage of each obvious clay m i n e r a l in the < 2# non-carbonate fraction. They total 100%. GIBILL, QUAILL, AMPILL a r e r e s p e c t i v e l y the gibbsite/illite, q u a r t z / i l l i t e , and a m p h i b o l e / i l l i t e peak height r a t i o s for the 2-20~ n o n - c a r b o n a t e fraction. CALCAR is the percentage calcium carbonate. element data with the mineralogical data that the mineralogical distributions are primarily latitud i n a l l y c o n t r o l l e d - m a i n l y r e f l e c t i n g i n t e n s i t y of weathering on the adjacent continents - while all the trace-element distributions except chromium and lead are controlled by longitudinal features. I t i s n o t s u r p r i s i n g t h e n t h a t no c o r r e l a t i o n w a s found in the statistical analysis between the mineralogy and the trace elements. The variables that might have been correlated, intuitively, are i l l i t e a n d c h r o m i u m i n t h a t t h e y b o t h a p p e a r to b e h i g h e r i n t h e n o r t h A t l a n t i c r e l a t i v e to t h e s o u t h A t l a n t i c . T h e r e i s no c o r r e l a t i o n , h o w e v e r , b e t w e e n t h e s e two v a r i a b l e s . Similarly l e a d s h o w s no a s s o c i a t i o n w i t h m i n e r a l o g y . The strongest correlations for the trace elem e n t s a r e two: (1) m a n g a n e s e , c o b a l t a n d n i c k e l a n d (2) c o p p e r a n d c a l c i u m c a r b o n a t e . T h e m a n ganese-cobalt-nickel association is obviously r e l a t e d to r e g i o n s of low c l a y a c c u m u l a t i o n [2, 6]
167
Depth (m) % CaCO 3 Pb Cr Cu Ni Co Mn Ba
95 o b s e r vations
252 o b s e r vations
4209 55.3 62 88 139 92 45 4508 1602
3920 48.3 52 80 115 79 39 3982
Wedepohl [9] compilation Atlantic
Pacific
45 86 130 140 38 4000 700
110 78 400 300 110 9400 6700
e s t i m a t i n g t h e r e l a t i v e r a t e s of c l a y a c c u m u l a t i o n i n t h e A t l a n t i c r e l a t i v e to t h e P a c i f i c a s s u g g e s t e d b y W e d e p o h l [9] o n t h e b a s i s of t r a c e element concentration differences between the s e d i m e n t s of t h e two o c e a n s i s d i s c u s s e d e l s e w h e r e [10]. W e t h a n k P r o f . M a u r i c e E w i n g , D i r e c t o r of the Lamont Geological Observatory (Columbia U n i v e r s i t y ) f o r t h e c o r e s a m p l e s u s e d in t h i s study. Carolyn Wellman assisted in the laboratory. This research has been supported mainly by the National Science Foundation Grant GP2456 to KKT.
References [1] K.K. Turekian and D . F . S c h u t z , in: Symposium on Marine Geochemistry, N a r r a g a n s e t t Marine Lab. Occas. Publ. No. 3 (1965) p. 41.
168
K.K. TUREKIAN and J. IMBRIE
[2] K.K. Turekian and E. H. Tauseh, Nature 201 (1964) 696; K.K.Turekian, Trans. N.Y. Acad. Sci. 26 (1964) 312. [3] E. D. Goldberg and G.O.S. Arrhenius, C,eochim. Cosmochim. Acta 13 (1958) 153. [4] P . E . B i s c a y e , Bull. Geol. Soc. Am. 76 (1965)803; P. E. Biscaye, Ph.D. Thesis, Yale Univ. (1964). [5] J. Imbrie and T. H. Van Andel, Bull. Geol. Soc. Am. 75 (1964) 1131; V. Manson and J. Imbrie, Karts. Geol. Survey Special Dist. Publ. 13 (1964).
[6] K. K. Turekian and M. Stuiver, Science 146 (1964) 55. [7] N. S. Skornyakova, Akad. Nauk SSSR No. 5 (1964) 3. [8] R. Revelle, M. Bramlette, G. Arrhenius and E.D. Goldberg, Geol. Soc. Am. Special P a p e r 62 {1955) 221. [9] K.H.Wedepohl, Geochim. Cosmochim. Acta 18 (1960) 200. [10] K.K.Turekian, in: The quaternary history of ocean basins, B.C. Heezen, ed. (INQUA Symp. Publ., in press).
T H E D I S T R I B U T I O N OF T R A C E E L E M E N T S IN D E E P - S E A S E D I M E N T S O F T H E A T L A N T I C OCF..AN K a r l K. TUREKIAN and John IMBRIE Department of Geology, Yale University, New Haven, Connecticut and Department of Geology, Columbia University, New York, New York Received 26 May 1966
The distributions of barium, cobalt, copper, nickel, lead, chromium, manganese and tin have been determined in the tops of deep-sea cores from the Atlantic Ocean. The trace elements show no correlations with clay mineralogy or depth of water. The strongest correlations are. (1) among manganese, nickel and cobalt which can be related generally to areas of low clay accumulation rates hence possibly representing a fine grained pelagic component, and (2) the correlation of copper with calcium carbonate.
A s y s t e m a t i c study of the t r a c e - e l e m e n t c o m position of the tops of c o r e s r a i s e d by the Lamont Geological O b s e r v a t o r y in the Atlantic Ocean has been made u s i n g an e m i s s i o n s p e c t r o graphic technique [1]. The e l e m e n t s d e t e r m i n e d w e r e b a r i u m , copper, cobalt, nickel, lead, c h r o m i u m , m a n g a n e s e and tin. As the c o n c e n t r a t i o n of tin was below the l i m i t of detection (2 ppm) in many c o r e s it is not included in the s t a t i s t i c a l a n a l y s i s d e s c r i b e d below and the r e sults a r e not r e p o r t e d h e r e although it should be noted that a random d i s t r i b u t i o n p a t t e r n a p p e a r s to exist for this element. Figs. 1-5 show the d i s t r i b u t i o n s of cobalt, nickel, m a n g a n e s e , c h r o m i u m and copper, on a c a l c i u m c a r b o n a t e - f r e e b a s i s , in the tops of c o r e s r a i s e d i n the Atlantic Ocean. Maps of the d i s t r i b u t i o n s of b a r i u m and c a l c i u m c a r b o n a t e have been r e p o r t e d p r e v i o u s l y [2]. T h e r e was no s t r o n g p a t t e r n to the lead d i s t r i b u t i o n , hence a map of it is not included. It is evident that cobalt, nickel, m a n g a n e s e and copper a r e p r e s e n t in higher c o n c e n t r a t i o n s in the m i d - o c e a n i c a r e a r e l a t i v e to the deeper a r e a s between the MidAtlantic Ridge and the c o n t i n e n t a l m a r g i n s . This is also t r u e of b a r i u m , g e n e r a l l y , and also of c a l c i u m carbonate. B a r i u m is known to be a s s o ciated with high biological activity in some p a r t s of the oceans [2, 3] and the c a l c i u m carbonate d i s t r i b u t i o n r e f l e c t s both i n t e n s e productivity and the a s - y e t - u n r e s o l v e d effects of water depth. In o r d e r to pick out p o s s i b l e a s s o c i a t i o n s of the t r a c e e l e m e n t s with each other, w a t e r depth, c a l c i u m carbonate, and m i n e r a l o g y , a s t a t i s t i c a l a n a l y s i s of the data was made. The object of
such an a n a l y s i s is to quantify and evaluate c o r r e l a t i o n s which a r e intuitively apparent as well as to focus attention on c o r r e l a t i o n s not c l e a r l y d i s c e r n e d . With such c o r r e l a t i o n s or a b s e n c e s of c o r r e l a t i o n s we can then p r o c e e d to draw i n f e r ences about the p r o b a b l e p r o c e s s e s operative to explain the o b s e r v e d d i s t r i b u t i o n s and a s s o c i a tions. The m i n e r a l o g i c a l data a r e those of B i s caye [4]. The t r a c e e l e m e n t and carbonate d e t e r m i n a t i o n s were made on the same sample on which the clay m i n e r a l o g y was d e t e r m i n e d . Two sets of data were analyzed by a s t a t i s t i c a l technique (factor analysis) d e s c r i b e d p r e v i o u s l y [5]: (1) a set of 95 c o r e s for which b a r i u m data as well as the other data were available, totalling 16 v a r i a b l e s ; and (2) a set of 252 c o r e s including all the v a r i a b l e s except b a r i u m , totalling 15. A p r i n c i p a l components factor a n a l y s i s indicates that t h e r e a r e e s s e n t i a l l y nine independent sets of influences o p e r a t i n g in both sets of data. A v a r i m a x rotation p r o c e d u r e f u r t h e r i n d i c a t e s that the nine v a r i a b l e s displaying g r e a t e s t mutual independence a r e those listed f i r s t in each c l u s t e r in table 1. The tabled values a r e s t a n d a r d i z e d p a r t i a l l i n e a r r e g r e s s i o n coefficients r e l a t i n g the nine s e l e c t e d v a r i a b l e s to each of the sixteen. Only the most significant coefficient is r e c o r d e d for each v a r i a b l e . The r e s u l t s have been r e corded in table 1 to b r i n g out groupings of v a r i a b l e s with s i m i l a r dependencies. The clay m i n e r a l o g i c a l s t a t i s t i c a l data a r e in t h e m s e l v e s not p a r t i c u l a r l y i n f o r m a t i v e s i n c e the d i s t r i b u t i o n maps of the m i n e r a l s have been adequately i n t e r p r e t e d by B i s c a y e [4]. It is obvious f r o m the v i s u a l c o m p a r i s o n of the t r a c e -
162
K.K. TUREKIAN and J. IMBRIE
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90
75
60
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75
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15
30
45
60
F i g . 1. M a p o f c o p p e r c o n c e n t r a t i o n in b o t t o m s e d i m e n t s o f t h e A t l a n t i c O c e a n calculated on a carbonate-free basis.
75
DISTRIBUTION OF TRACE ELEMENTS
105
90
75
60
45
30
15
IN D E E P - S E A
0
15
SEDIMENTS
30
163
45
60
60 !:.-.-$'/
..'i
75
60
,B,
iiii!!iiiiii!ii 45
45
30
30
I..,
°
Q
U
30
30
•
45
:
".
" .
/
•
.
PPM
/:
Cobalt
t
lip
(carbonate
I
- free)
45
2 - zo 20 - 40 40 - 80
"
60 o • 105
90
75
6O
" 45
30
15
0
t5
l l
8 0 - 160
l l
160 ° 3 2 0
30
45
F i g . 2. M a p o f c o p p e r c o n c e n t r a t i o n in b o t t o m s e d i m e n t s o f t h e A t l a n t i c O c e a n calculated on a carbonate-free basis.
60
6O
75
164
K . K . T U R E K I A N and J. IMB R IE
105
90
75
60
45
30
15
0 I
30
45
60
75
e Q
60
60
45
45
30
30
o
0
~)
30
0 •
0
e
PPM Nickel
45
I lip
" t:
(carbonate -free)
J
45
o-4o 40 - 80
%
8 0 - 160
1 1
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60
Q~ 0
105
90
7'5
60
45
30
15
0
15
3O
1 6 0 - 3,20 60
>
320
45
F i g . 3. Map of n i c k e l c o n c e n t r a t i o n in b o t t o m s e d i m e n t s of t h e A t l a n t i c O c e a n c a l c u l a t e d on a c a r b o n a t e - f r e e b a s i s .
6O
75
DISTRIBUTION
105
90
75
60
OF TRACE
45
ELEMENTS
30
i5
IN DEEP-SEA
0
15
SEDIMENTS
30
165
45
60
75
r~
60 .
.
.
.
.
.
.
.
.
.
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.
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.
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.
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.
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.
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45
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============================================================
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30
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45
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PPM
Manganese (carbonate-free) I
45
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lip
IO00 - 5 O 0 0 5000 - I0,000
1
60
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60
e 105
90
75
60
45
30
15
0
15
Fig. 4. Map of manganese concentration in bottom sediments calculated on a carbonate-free basis.
30
of the Atlantic
4~
Ocean
60
75
166
K.K. TUREKIAN and J. IMBRIE
105
90
75
60
45
30
t5
0
t5
30
45
60
60
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75
60
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I 75
l
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l
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O
F i g . 5. M a p of c h r o m i u m c o n c e n t r a t i o n in b o t t o m s e d i m e n t s c a l c u l a t e d on a c a r b o n a t e - f r e e b a s i s .
I 15
I 30
I 45
of the A t l a n t i c O c e a n
I
75
DISTRIBUTION OF TRACE ELEMENTS IN DEEP-SEA SEDIMENTS Table 1 Results f r o m oblique projection m a t r i c e s (expressed as p a r t i a l l i n e a r r e g r e s s i o n coefficients) *. Variable No.
Including b a r i u m (sample = 95)
Excluding b a r i u m (sample = 252)
1
MANGAN NICKEL COBALT
1.000 0.914 0.764
NICKEL MANGAN COBALT
1.000 0.884 0.851
2
GIBILL KAOLIN
1.000 0.892
KAOLIN GIBILL CHLOR
1.000 0.670
-0.561
3
QUAILL AMPILL
1.000 0.860
QUAILL
1.000
4
MONT ILLITE CH LOR
1.00O -0.724 -0.794
MONT ILLITE
5
CALCAR COPPER
1.000 0.671
CALCAR COPPER
1.000 -0.827 1.000 0.846
6
LEAD
1.000
LEAD
1.000
7
CHROMI
1.000
CHROMI
1.000
8
DEPTH
1.000
DEPTH
1.000
9
BARIUM
1.000
AMPILL
1.000
a n d i s p r o b a b l y d u e to t h e d e p o s i t i o n of f i n e m a t e r i a l w i t h h i g h c o n c e n t r a t i o n s of t h e s e e l e m e n t s transported from the continents. A similar dist r i b u t i o n h~as b e e n o b s e r v e d f o r M n i n d e e p - s e a s e d i m e n t s of t h e P a c i f i c O c e a n b y S k o r n y a k o v a [7]. T h e c a l c i u m c a r b o n a t e i s a r e f l e c t i o n of t h e preserved productivity and although copper is n o t i n t h e l a t t i c e of t h e c a r b o n a t e t e s t s , i t i s i n s o m e way b i o l o g i c a l l y a s s o c i a t e d a n d e x t r a c t e d from sea water and preserved with the calcium c a r b o n a t e f r a c t i o n . R e v e l l e e t al. [8] a l s o n o t e d this qualitatively for Pacific sediments. The average trace-element concentration values for the Atlantic Ocean deep-sea clay sediments based on these results are compared with Wedepohl's averages for the Atlantic and Pacific in t a b l e 2. A d i s c u s s i o n of t h e b e a r i n g o f t h e s e r e sults on material balance type calculations in Table 2 T r a c e element concentrations in p a r t s p e r million. Present results Atlantic
* The code n a m e s for the v a r i a b l e s have the following meanings: MANGAN, NICKEL, COBALT, LEAD, BARIUM, CHROMI, COPPER stand for the concent r a t i o n s of the obvious t r a c e e l e m e n t s on a calcium c a r b o n a t e - f r e e b a s i s . KAOLIN, MONT, ILLITE, CHLOR r e p r e s e n t the percentage of each obvious clay m i n e r a l in the < 2# non-carbonate fraction. They total 100%. GIBILL, QUAILL, AMPILL a r e r e s p e c t i v e l y the gibbsite/illite, q u a r t z / i l l i t e , and a m p h i b o l e / i l l i t e peak height r a t i o s for the 2-20~ n o n - c a r b o n a t e fraction. CALCAR is the percentage calcium carbonate. element data with the mineralogical data that the mineralogical distributions are primarily latitud i n a l l y c o n t r o l l e d - m a i n l y r e f l e c t i n g i n t e n s i t y of weathering on the adjacent continents - while all the trace-element distributions except chromium and lead are controlled by longitudinal features. I t i s n o t s u r p r i s i n g t h e n t h a t no c o r r e l a t i o n w a s found in the statistical analysis between the mineralogy and the trace elements. The variables that might have been correlated, intuitively, are i l l i t e a n d c h r o m i u m i n t h a t t h e y b o t h a p p e a r to b e h i g h e r i n t h e n o r t h A t l a n t i c r e l a t i v e to t h e s o u t h A t l a n t i c . T h e r e i s no c o r r e l a t i o n , h o w e v e r , b e t w e e n t h e s e two v a r i a b l e s . Similarly l e a d s h o w s no a s s o c i a t i o n w i t h m i n e r a l o g y . The strongest correlations for the trace elem e n t s a r e two: (1) m a n g a n e s e , c o b a l t a n d n i c k e l a n d (2) c o p p e r a n d c a l c i u m c a r b o n a t e . T h e m a n ganese-cobalt-nickel association is obviously r e l a t e d to r e g i o n s of low c l a y a c c u m u l a t i o n [2, 6]
167
Depth (m) % CaCO 3 Pb Cr Cu Ni Co Mn Ba
95 o b s e r vations
252 o b s e r vations
4209 55.3 62 88 139 92 45 4508 1602
3920 48.3 52 80 115 79 39 3982
Wedepohl [9] compilation Atlantic
Pacific
45 86 130 140 38 4000 700
110 78 400 300 110 9400 6700
e s t i m a t i n g t h e r e l a t i v e r a t e s of c l a y a c c u m u l a t i o n i n t h e A t l a n t i c r e l a t i v e to t h e P a c i f i c a s s u g g e s t e d b y W e d e p o h l [9] o n t h e b a s i s of t r a c e element concentration differences between the s e d i m e n t s of t h e two o c e a n s i s d i s c u s s e d e l s e w h e r e [10]. W e t h a n k P r o f . M a u r i c e E w i n g , D i r e c t o r of the Lamont Geological Observatory (Columbia U n i v e r s i t y ) f o r t h e c o r e s a m p l e s u s e d in t h i s study. Carolyn Wellman assisted in the laboratory. This research has been supported mainly by the National Science Foundation Grant GP2456 to KKT.
References [1] K.K. Turekian and D . F . S c h u t z , in: Symposium on Marine Geochemistry, N a r r a g a n s e t t Marine Lab. Occas. Publ. No. 3 (1965) p. 41.
168
K.K. TUREKIAN and J. IMBRIE
[2] K.K. Turekian and E. H. Tauseh, Nature 201 (1964) 696; K.K.Turekian, Trans. N.Y. Acad. Sci. 26 (1964) 312. [3] E. D. Goldberg and G.O.S. Arrhenius, C,eochim. Cosmochim. Acta 13 (1958) 153. [4] P . E . B i s c a y e , Bull. Geol. Soc. Am. 76 (1965)803; P. E. Biscaye, Ph.D. Thesis, Yale Univ. (1964). [5] J. Imbrie and T. H. Van Andel, Bull. Geol. Soc. Am. 75 (1964) 1131; V. Manson and J. Imbrie, Karts. Geol. Survey Special Dist. Publ. 13 (1964).
[6] K. K. Turekian and M. Stuiver, Science 146 (1964) 55. [7] N. S. Skornyakova, Akad. Nauk SSSR No. 5 (1964) 3. [8] R. Revelle, M. Bramlette, G. Arrhenius and E.D. Goldberg, Geol. Soc. Am. Special P a p e r 62 {1955) 221. [9] K.H.Wedepohl, Geochim. Cosmochim. Acta 18 (1960) 200. [10] K.K.Turekian, in: The quaternary history of ocean basins, B.C. Heezen, ed. (INQUA Symp. Publ., in press).