The California Emergency Management Agency (Cal EMA) issued a warning to operational Red Cross areas throughout the state yesterday after a 4.8 magnitude earthquake that occurred three miles south of Bombay Beach, Imperial County at 4:55 am. Although there were no damages or injuries reported as a result of this event, The U.S. Geological Survey has been tracking an "unusual sequence" of over 50 aftershocks, that have been clustered about 1 to 3 kilometers southwest of a projected extension of the San Andreas Fault, in the Salton Sea area. The majority of the magnitudes have been less than 2.5, although ABC has reported magnitudes as high as 3.5. Cal EMA recommended to the Red Cross that operational areas reach out to raise awareness of the events, and "ensure the readiness of systems essential to emergency operations".
Out lesbian Kate Hutton, aka The Earthquake Lady, is the CalTech Seismologist who is constantly sought by the media for her professional commentary regarding major Earthquakes, especially in Southern California.
"Swarms in the Imperial Valley are not a big deal," she said in regards to the Salton Sea quakes. "We're used to that. The reason that this one, and another one in 2001, got significant attention from us is that it's very close to the San Andreas Fault."
The San Andreas Fault is the notorious fault that falls on a tectonic plate which links the Pacific Plate and the North American Plate.
Cal EMA said in their issued warning:
Based on scientific data, and the fact that these most recent earthquakes have been in close proximity to the San Andreas Fault, there is increased concern that these earthquakes could trigger a large earthquake (M7.0 +) on the San Andreas itself. Historically, a major earthquake on this southern portion of the San Andreas Fault has not occurred in over 300 years, so the probability of a large earthquake is thought by seismologists to be higher than on portions of the fault that have ruptured more recently (e.g. in 1857 and 1906).Just a few months ago The Great Southern California Shakeout simulated what would happen if that happened on the San Andreas Fault.
Kate Hutton said:
"The fictional 7.8 earthquake that was the scenario for the shakeout drill started right here, OK? And this whole section hasn't broken since 1680, probably, so that's the reason for the close eye that we keep on it. It's another straw on a camel's back, but we don't know how many are there and we don't know how many a 'camel' can hold."As each day passes the risk of a large San Andreas earthquake decreases.
Cal EMA says that they will continue to monitor the situation and keep in contact with CEPEC scientists over the next few days.