Theoretical stress conditions in the matrix around a rigid circular inclusion and their geological implications

Abstract

Equations are derived which describe the stress condition in the matrix around a rigid circular inclusion subjected to uniaxial stress. The values of the principal stresses and their orientations are obtained using a computer. The orientation of potential fractures around an inclusion is determined from the stress trajectories and the development of pressure shadows and pressure fringes are predicted by assuming that mineral migration occurs in response to gradients in the mean stress. The type of structures (whether pressure shadows or pressure fringes) that develop in the low mean stress zone adjacent to the inclusions is controlled by the magnitude of applied stress.