Tremors under San Andreas studied

BERKELEY, Calif., Dec. 10 (UPI) -- Seismologists at the University of California are studying mysterious tremors deep under the San Andreas Fault that may signal future earthquakes.

The continuous tremors are "a kind of chatter" emanating from a depth far below the surface, generally five times deeper than the average quake on this segment of the fault, says study leader Robert M. Nadeau, an assistant research seismologist at the Berkeley Seismological Laboratory.

The faint tremors, which were detected beneath the town of Cholame, 15 miles southeast of Parkfield, are similar to those discovered in the past two years in Japan and the Pacific Northwest.

This is the first time, however, that such tremors have been recorded under a transform fault.

"This is new information from an area deep down under the fault we have not been able to look at before," Nadeau said. "If these tremors are precursory to earthquakes, there is potential here for earthquake forecasting and prediction."