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Geoinformatika 2015; 4(56) : 35-42 (in Ukrainian)

MODELING OF A WAVE FIELD PERTURBED BY LOCAL SOURCES IN VERTICALLY INHOMOGENEOUS HALF-SPACE AND CALCULATION OF SYNTHETIC SEISMOGRAMS

R.M. Pak

Hetman Petro Sahaidachny Army Academy, 32 Heroes of Maidan Str., Lviv 79012, Ukraine, e-mail: rpak@email.ua

Purpose. The aim of the article is to develop methods calculate seismic waves perturbed by local sources in a vertically inhomogeneous medium. For this purpose the following tasks are set: to implement mathematical modeling process of disturbance and propagation of seismic field in a horizontal layered isotropic elastic medium; to construct an algorithm and a program for numerical calculation of synthetic seismograms; to conduct computational experiments for verification.
Design/methodology/approach. The suggested methodology is based on the usage of Bessel-Mellin integrals, Thomson-Haskell matrix method and its modifications.
Findings. We developed analytical approach to modeling of waves in vertically inhomogeneous isotropic elastic environments. It permits to analyze the influence of changing environmental parameters and sources in the form of concentrated arbitrarily directed forces on synthetic seismograms. We created an algorithm and a program to calculate synthetic seismograms at a free surface medium.
Practical value/implications. The methodology presented here enables wave processes occurring in layered medium to be conducted both analytically and numerically. The calculation of synthetic seismograms and allocation of various types of waves in them enable a wave pattern recorded during seismic observations to be analyzed and accurately interpreted.

Keywords: mathematical modelling, seismic wave-field, matrix method, vertically heterogeneous medium, tensor of seismic moment, synthetic seismogram.

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