The stresses around a fault or crack in dissimilar media

In order to investigate some problems of geophysical interest, the usual consideration of symmetrical or antisymmetrical loading of an isotropic homogeneous plate containing a crack was extended to the case where the alignment of the crack separates two separate isotropic homogeneous regions. It develops that the modulus of the singular behavior of the stress remains proportional to the inverse square root of the distance from the point of the crack, but the stresses possess a sharp oscillatory character of the type r^(-1/2) sin (b log r), which seems to be confined quite close to the point, as well as a shear stress along the material joint line as long as the materials are different. The off-fault areas of high strain energy release reported by St. Amand for the White Wolf fault are qualitatively shown to be expected