Hi All. This may come as close as anything to prediction for a major quake in Southern California. Take Care…Don in creepy town

The correspondence between seismicity and the Coulomb failure stress changes produced by the Landers and earlier events suggests that regions of predicted increase are candidates for future major events. To predict how the Landers earthquakes have advanced or delayed the next great southern San Andreas earthquake, we let a frictionless San Andreas slip freely to relieve the stress imposed by the Landers and surrounding earthquakes (Fig. 4B). The immediate response is slip of 20 cm over 30 km of the central San Bernardino segment (equivalent to a M=6.2 event if it occurred seismically), and 7 cm in the northern Coachella Valley segment (equivalent to M=5.7). Thus San Andreas fault slip with a moment equivalent to two moderate events are needed simply to relieve the stresses added by the recent earthquakes. In contrast, a load comparable to a M=6.2 event is removed from the Mojave segment, and a M=6.0 load is removed north of Palm Springs (20), taking these portions of the fault farther from failure. After relaxation of the viscous substrate in our idealized plate model, the stress change on the San Andreas and surrounding faults roughly doubles (Fig. 4A, orange curve), as stress is transferred from the base of the fault back to the upper crust. Similarly, the slip required to relieve the stresses also rises (Fig. 4B, orange fields). The calculated slip does not depend on the number of segments allowed to slip at once. So far no creep has been measured (21) and no moderate earthquakes have occurred on these faults since the Landers event. If these events do not take place, the likelihood of great earthquakes on the San Andreas must rise as well.

• Coulomb Failure