Earthquake prediction and rock mechanics. Contribution to current research in geophysics

23A

sions o n t h e implications of t h e work for seismic probing a h e a d a t u l t r a s o n i c f r e q u e n c i e s add on ultrasonic evaluation of rock quality in a t u ~ m 6 context.

move indepemdently and with different velocities, ereatir~ a zone of shearing movement. The eml~hasis of this paper is on the character of the evidence, its implications tO salt-dome geology, and how spines might affect the surrounding sedimentary rocks.

Geology

Tectonic process

772058 CGRRELR~ION ~ LENGTH AND OFFSET IN STRIEE- SLIP FAULTS Radii, G Tectonophysics, V37, ~ , 2 Feb I977,~TI-T7

772063 FOLD DEVELOPMEN~ IN THE JURA Laubscher, H P Tectonophysics, V37, N4, 2 Feb 1977, P337-

362 Describes the general situation at the onset of foldir6, based on mapping anl stratigraphic analysis, in terms of tectonostatics. The discussion is in terms of cross sections with occasional outlooks into the third dimension, and the scale is restricted to lO-lO00m.

Strike-sllp faults in continental crust are shown to exhibit non-lineer positive correlation between length add offset. This cO~relation can be empirically explained as the co,bided effect of the changes in the growth rates of offset amd length durimg the time of tectonic activity of a fault. 772059 MATHEMATICAL MCDEL FOR 0RIERTATION DATA FRCM MACROSCOPIC CYLINDRICAL FOLDS Kelker s D; Lamgenberg, C W J Int Ass Math Geol, V8, NS, Oct 1976,

~549-559 Discusses the use of Bir~am's distribution for amalyzir~ orientation data from a cylindrically folded surface. Parameters of the distribution give information o n the spatial attitude, shape amd s y m n e t ~ y of the fold, b u t not on the size or tightness

of the fold.

Earthquake mechanisms and effects

772~

LONG AND SHORT THeM EARTHQUAKE PREDICTION IN KAMCHATKA Fedotov, S A; Sobolev, S A; Boldyrev, A A Tectonophysics, V37, E%, 2 Feb 1977, I>305321 Presents the results of long-areal sheet-term earthquake prediction obtained durir~ 19711974.

With

a probability distribution fitted to the fold it is possible to test hypotheses such as whether two folds, or two segments of t h e same fold, have the same fold axis.

772065 TIME-D(IWAIN D E T O N A T I O N OF EARTHQUAKE FAULT P A R A M E ~ S FR(~ SHCRT PERIOD P-WAVES Somerville, P G; Wi~ins, R A; Ellis, R M Bull Seismol Soc Am, V66, ~ , Oct 1976, P1459-

1484 772060 GEOLOGICAL IMPLICATIONS OF SI~EADY S T ~ E MECHANISMS IN CATASTROPHE THEORY Cubitt, J M; Shaw, B J Int Ass Math Gecl, V8, N6, Dec 1976, P657-

662 Gives a brief introduction to catastrophe theory and outlines the problem of equilibri~n as it relates to geological application of the theory. Illustrates a proposed solution to this by a model for sediment transport on t h e continental slope • 772061 CATASI~OPHE THEORY MODELS IN GEOLOGY Henley, S J Int Ass Math Geol, VS, N6, Dec 1976, P649-

6~5 Catastrophe theory is a recently developed branch of topology which has a nt~nber of practical applications, principally because of its ability to model situations which include discontinuities cr slDgularitles, where the methods of differential calculus break down. Outlines of how the theory may be applied to volcanic ash and nuees ardentes, turbiditles add fault movement ere given. "r72~2 SHEAR ZONES INSIDE GULF COAST SALT STOCKS HELP TO DELINEATE SPINES OF MOVEMENT Ku~fer, D H Am Ass Petrol Geol Bull, V60, ~ , Sept 1976,

n434-1~7 In the course of mapping salt structures in the salt mines of Louisiana add elsewhere, evidence has been four~ to confirm the idea that discrete masses of salt called s~Ines,

Source parameters of two shallow earthquakes have been determined by the time-domaln armlysis of short-period teleseismic reccm~lirgs, the objective being to investigate whether a shear dislocation model of earthquake rupture can describe the teleseimuically recorded short-period radiation of earthquakes having SmS11 sot~ce dimensions. 772066 EARTHQUAKE PREDICTION AND ROC~ ~CHANICS. CONTRIBL~ION TO CURREET RE~a/~CH IN GEOPHYSICS Wys,, M (editor) Basle: Birkhauser Verlag, 1975 , 330P A collection of 28 papers on the behaviour of rocks under load in lab test conditions, on field observations of precursors of tectonic shocks and on theories amd models of earthquake precursory phenomena, reprinted from Pure and Applied Geophysics, Vol 113, 1975.

Underground Excavations 772067 LANCA~A'~ DEBUT FOR ROCK BORING RIG Ground Emgng, VlO,NI, Jan 1977, PS9-40 Briefly describes Pigctt Foundations Lid new bedim6 rig which is capable of drillimg in a single pass holes up to 8ft in diameter or to