July 1986 was an unusually active month for moderate to strong earthquakes in California , with three events occurring in less than two weeks . Each had mild to moderate effects and began on July 8 with the event near Palm Springs . The second event was a M5 .8 shock that occurred off the coast of Oceanside on July 13 . While the earthquake off the southern California coast occurred in an area thought to be capable of generating a tsunami , the earthquake near Palm Springs occurred on a portion of the southern San Andreas Fault system that has been designated a seismic gap and is a likely location for a very large future earthquake . The Chalfant Valley earthquake occurred on July 21 along the White Mountains Fault Zone near Bishop
Chalfant Valley earthquake
1986 Chalfant Valley earthquake
1986 North Palm Springs earthquake