Va. Potapov et al., Problems of quantitative estimation of seismic effects in pleistoseistic regions of strong earthquakes, GEOL GEOFIZ, 39(8), 1998, pp. 1141-1150
A forecast of seismic effects in pleistoseistic regions is connected with e
stimation of the intensity of nonlinear waves in half-space rocks in the vi
cinity of earthquake focus zones. The formalized parameters of earthquake f
oci - sources of elastic (seismic) waves - are Insufficient for solving pro
blems of engineering seismology. This paper studies in detail the character
istics of rocks in the zones of nonelastic focus deformation. Analysis of e
xperimental data and theoretical generalizations permitted determination of
the integral level of wave amplitudes up to fault zones, the generalized f
orm of spectra, and the emission duration, as well as establishment of the
correlation between the intensity of elastic-plastic waves and reduced dist
ances. Also, the relative dimensions of the zones of the nonlinear deformat
ion of earthquake foci have been determined. It is shown that an earthquake
focus, as a source of elastic waves, may be represented as an ellipsoid. T
he authors have determined the focus dimensions and performed their correla
tion with a mean radius Ro - a magnitude conjugated with the length of the
predominant wave of a source. It is shown that an increase in the accuracy
of the forecast of seismic effects in pleistoseistic regions depends on the
reliability of determining the dimensions and characteristics of nonlinear
deformation. For forecasting seismic effects in the context of the energet
ic criteria of strength, the coefficients of elastic-system dynamicity have
been obtained.