On some problems related to soil failures and intensity evaluations. Short communication

174A and locations of these latter failure surfaces are almost unaffected by the presence of failure surfaces caused by the initial fault movement. Ground surface expressions in alluvium associated with movements on dip-slip faults are summarized. Three field cases are reviewed and related to the experimental observations and the proposed simple model. This model is used to predict shapes and locations of failure surfaces in alluvium overlying dip-slip faults. Model predictions compare favourably with observations from the field. Auth. 845O95 Tectonic stress field in East Eurasia Eguchi, T Phys Earth Planet Inter V33, N4, Dec 1983, P318-327 845O96 Fault mechanism in the Toledo shear zone in Spain Hernandez-Enrile, J L Proc 5th Congress of the International Society for Rock Mechanics, Melbourne, 10-15 April 1983 V2, PF75-F78. Publ Rotterdam: A. A. Balkema, 1983 The microstructural development of the mylonite present in the Toledo shear zone has been examined in order to establish a macroscopic fracture mechanism. Microstructural development has occurred through dynamic recovery and dynamic recrystallization of the grains of the minerals present. The Toledo shear zone has developed under steady strain rates of aseismic shear. 845097 Measurements of tectonic stresses, strain rates related to active faults and observed earthquakes around large caverns Kanagawa, T; Komada, H; Hayashi, M Proc 5th Congress of the International Society for Rock Mechanics, Melbourne, 10-15 April 1983 V2, PF85-F88. Publ Rotterdam: A. A. Balkema, 1983 On the basis of approximately 20 experiments of tectonic stress measurements in large underground excavations and active faults the suitability of employing the acoustic emission method and a miniaturization of the overcoring method, as well as the effects of tectonics, topography and faults, are examined. Moreover, the connection between the geodetically ascertained shear strain rate in Japan and the range of historically observed earthquakes over the past 1200 years in the surroundings of underground power stations is discussed. Auth. 845098 Mechanisms of the deformation of the earth's crust - induced structures and anisotropy (In French) Deramond, J; Sirieys, P; Soula, J C Proc 5th Congress of the International Society for Rock Mechanics, Melbourne, 10-15 April 1983 V2, PF89.F93. Publ Rotterdam: A. A. Balkema, 1983 The deformation of the earth's crust appears as continuous (viscous or plastic flow) or discontinuous fracturing. Its mechanisms have been investigated with emphasis on the role of the structure of the deformed medium (strain induced or preexisting structure) which can be active or passive. Laboratory experiments on rock samples and analogical models are interpreted and applied to natural examples from the Pyrenees and the southern French Massif Central, relating to the opening of sedimentary basins and the sliding-spreading of nappes. Auth.

845O99 Rock mechanics and mathematical models applied to geology (In French) Quiblier, J A; Ngokwey, K Proc 5th Congress of the International Society for Rock Mechanics, Melbourne, 10-15 April 1983 V2, PF191-F194. Publ Rotterdam: A. A. Balkema, 1983 A large-deformation viscoelastic mathematical model applied to the overthrusting of two plates of the earth's crust clearly illustrates the deformation of the sedimentary cover and can be used to analyse various parameters. An elastic model applied to a fault can be used to determine the thrust that caused the fault to be propagated. Auth, Environmental effects, weathering and soil formation

See: 845348 Earthquake mechanisms and effects

See also: 845048, 845075 845100 Determination of seismic reference motion for nuclear sites in France Levret, A; Mohammadioun, B Engng Geol V20, N1-2, March 1984, P25-38 The Nuclear Safety Department in France has developed a method for site-specific hazard assessment, entailing the definition of specific reference motions. Seismotectonic criteria are used to define a site's reference earthquake, then corresponding ground motions are obtained by: (1) a thorough analysis of macroseismic data to define the characteristics of reference events; (2) calculation of ground motion from a statistical study of strong-motion records collected in a data bank, based on correlations between response spectra, magnitudes, focal distances and macroseismic intensities, corresponding to the records. A valid approach has recently been sought for taking nearby, lowmagnitude earthquakes into account, due to the high ground accelerations with which they are associated. 845101 Relations between ground motions and earthquake magnitude, focal distance and epicentrni intensity Schenk, V Engng Geol II20, 311-2, March 1984, P143-151 845102 On some problems related to soil failures and intensity evaluations. Short communication Gurpinar, A Engng Geol }'20, N1-2, March 1984, P181-185 The use of intensity values to describe seismic effects expected at a given site has become of significant engineering design interest. One problem area is the damage caused on soils of different quality. It is then important to separate the damage due to soil amplification from that of soil failure. Examples from recent earthquakes are given for illustration purposes. 845103 Seismic disturbance of 1976 March 20, East Kazakhstan: earthquake or explosions? Research note Pooley, C I; Douglas, A; Pearce, R G Geophys J R Astr Soc V74, N2, Aug 1983, P621-631