The Mechanics of Oblique Slip Faulting

Summary The various mechanisms which could cause oblique slip faulting are briefly reviewed. It is thought that such faulting may frequently arise from the existence of preferred planes of fracture within the rocks. The dynamics of this mechanism is studied in some detail and an expression is obtained for the first direction of slip within the plane under the influence of a general stress system of given orientation it is found that the initial slip may occur in any possible direction within the plane, the direction depending on the relative values of the three principle pressures. The theory suggests that when a pre-existing fault is subjected to a reorientated stress system (typical or rotated) the movement after fracture will usually be oblique. In conclusion, the general implications of the theory are discussed.