Grid-characteristic method using superimposed grids in the problem of seismic exploration of fractured geological media

Abstract

Introduction.Seismic exploration in conditions of heterogeneity of the environment is an urgent topic for the oil and gas industry. Consequently, the development of numerical methods for solving the direct problem of seismic exploration remains relevant as a necessary link in the development and improvement of methods for solving the inverse problem. The Schonberg thin crack model has performed well in the numerical solution of problems requiring explicit consideration of geological inhomogeneities.Materials and Methods. In this paper, we consider a modification of the grid-characteristic method using superimposed grids. The presented approach makes it possible to conduct computational experiments, explicitly taking into account fractured inhomogeneities with arbitrary spatial orientation. For this, in addition to the basic regular computational grid, there is the concept of superimposed grids. Inhomogeneities, such as cracks, are described within the framework of the superimposed grid and, in turn, have no restrictions associated with the main grid. Thus, by performing an interpolation operation between the superimposed main grids, we can bypass the requirement of alignment of cracks and edges of the main grid.Results. The proposed approach made it possible to study the dependence of the anisotropy of the seismic response of a fractured cluster on the dispersion of the angles of inclination of the cracks.Discussion and Conclusions. A modification of the grid-characteristic method using superimposed grids is proposed to explicitly account for fractured inhomogeneities in a heterogeneous geological environment.