Quake Swarm Continues With 24 SoCal Temblors
Wednesday, Mar 25, 2009 | Updated 7:20 AM PDT
Getty Images/David McNew
A quake California's Imperial County, 90 miles east of San Diego, on Tuesday morning, but it's not clear how a swarm of recent quakes might affect the San Andreas fault.
More than a score of earthquakes, including one capable of causing moderate damage, rattled the Salton Sea area Tuesday morning during a period in which scientists are watching to see if small faults under the lake are transferring energy to the more dangerous San Andreas fault.
The biggest of the 24 quakes recorded Tuesday morning was a magnitude-4.8 shaker at 4:55 a.m., its epicenter 3 miles south of Bombay Beach and 90 miles east-northeast of San Diego, according to the U.S. Geological Survey. But most of the temblors recorded between 4:58 a.m. and 6:14 a.m. around Bombay Beach were under a 3 magnitude.
Scientists are particularly interested in the area because an earthquake that starts in Bombay Beach in Imperial County and ripples northwest along the San Andreas fault could be the Big One that devastates Los Angeles, Graham Kent, a research geophysicist at UC San Diego, told the Los Angeles Times.
The quakes appeared to be tapering off by Monday afternoon, according to the monitoring system run by the USGS and Caltech in Pasadena.
In a 48-hour period starting Saturday morning, 42 quakes shook just south of Bombay Beach on the Salton Sea, ranging in magnitude from 0.5 to 3.3. These quakes appear to be taking place at the hazy intersection of several recently mapped faults crossing beneath the Salton Sea and the the San Andreas fault, according to the newspaper.
The worry for scientists comes from a case in 1987, when a magnitude-6.2 earthquake on one of the crossing faults appeared to trigger a 6.6 quake 12 hours later on the Superstition Hills fault to the south.
But the the last time a swarm of this type occurred in the area was 2001, so they are not especially unusual, Caltech seismologist Kate Hutton told The Times. She said scientists do not yet know if quakes this small can trigger anything dangerous on the San Andreas.
Tuesday the American Red Cross to encouraged Coachella Valley residents to be prepared for a bigger earthquake that could strike at any time.
Residents should put together an earthquake kit, have a disaster plan and know their city's disaster plan, according to Randy Phillips, an instructor for the Red Cross in Riverside.
"If you're not prepared, you're going to be more apt to panic, not know what to do, what to take and trying to plan all of that in some short urgent time frame rather than being prepared and following your system," Phillips said.
People should also make a plan for what to do during any disaster, not just earthquakes, Phillips said.
"A couple things people forget are medications, some extra clothing and some cash," Phillips said.
More information about disaster preparedness can be found at the American Red Cross' Web site at www.redcross.org.
