System and method for estimating subsurface principal stresses from seismic reflection data

Abstract

A method and system is described for estimating stress characteristics from seismic data. The method includes receiving seismic data acquired over a region, receiving properties of rock at a location within the region, and estimating one or more stress characteristics for a sub-region by combining the seismic data and the rock properties using a relationship between the stress characteristics in the sub-region and elastic stiffness and/or sonic velocity in the sub-region. The relationship is based on a non-linear elasticity theory. The described system and method also includes analyzing in the seismic data azimuth and offset dependence of seismic signatures for seismic anisotropy thereby determining a set of anisotropic coefficients; identifying directions of minimum, intermediate and maximum stresses from orientation of principal axes of seismic anisotropy and signs of the anisotropic coefficients; and inverting the anisotropic coefficients thereby estimating magnitudes of principal stresses in the sub-region using non-linear elastic constants and vertical total stress information derived from the rock properties.