Poroelastic coupling between the 1992 Landers and Big Bear earthquakes

A three-dimensional finite Element modal was constructed to investigate the significance of poroelastic coupling between the 1992 Landers and Big Bear earthquakes in southern California. The homogeneous poroelastic model pred icted a maximum increase in left lateral slip potential (change in shear st ress less the change in effective fault normal stress scaled by a coefficie nt of friction) along the southwest part of the Big Bear fault, consistent with the epicentral location. In contrast, slip potential calculated for a weak fault zone in a state of isotropic stress for drained conditions, indi cated a maximum increase along the northeast part of the Big Bear fault.