Hello Ladies,

Those quakes are happening at the southern terminus of the Clark Lake segment of the San Jacinto fault. That area is known as the Borrego Badlands, a region of very rapid erosion due to a lack of plant life. That area is a geologic wonderland. A few years back, San Diego State had a team out there recovering the remains of a mastadon. Also very close to these quakes is an area of older alluvium where Cahuilla Indians had fish traps during the larger inundations of Lake Cahuilla. My guess is that there are a number of blind step over faults much like the faults at Elmore Ranch further south. I'll get some more on this.