Abstract:
Geoacoustic emission is the process of elastic wave generation by rocks as the result of dynamic reconstruction of their structure. Observation results show that mechanic processes, occurring in the source of a preparing earthquake, affect the geoacoustic emission dynamics. Modeling of geoacoustic emission zones, the regions of the earth crust surface with deformations of the order 10$^(-8)$–10$^(-5)$, has been earlier carried out to prove the relation between geoacoustic emission variations and the process of earthquake preparation. Results of the modeling, which was performed earlier, show that the level of calculated deformations at observation sites exceeds the tidal ones but differs by one order from the recorded deformations. This may be associated with the fact that the earth crust was considered as a homogeneous environment. In reality, the earth crust consists of rock layers, some part of which has supercritical state and manifests plastic and quasi-plastic properties. The present paper is devoted to the modeling of the earth crust inhomogeneities impact on spatial distribution of geoacoustic emission zones. Inhomogeneities are described by simple force system distributed over spherical inclusion surface. Intensity of the force action was assumed to be constant. Solutions for the boundary problem of elasticity linear theory were obtained in the form of Green's functions convolution for homogeneous isotropic elastic half-space. Computational experiments were carried out, and lines of the field component levels of the displacement vectors of the earth crust surface were constructed. It was shown that spherical inclusions affect displacement vector field of the earth crust surface. The impact character depends on the number of inhomogeneous inclusions and their locations relative to the source of a preparing earthquake.
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