The survey also said there was a second aftershock in the region that registered 1.8 on the Richter scale this morning..
Bob Egelko of the San Francisco Chronicle reports this morning:
The Contra Costa and Alameda County sheriff's offices said they had no reports of damage.
The quake was felt in Petaluma to the north and in Gilroy and Turlock to the south and southeast, said David Oppenheimer, a seismologist with the geological survey. He said it occurred on an unnamed fault about 2.5 miles from the larger Calaveras fault and two miles north-northeast of Alamo, on Serafix Road.
A cluster of quakes occurred on the same fault in April 1990, with 18 registering at 3.0 or higher in a three-week period, Oppenheimer said. He said the larger quakes in that sequence caused minor structural damage to nearby homes.
Friday's earthquake took place about 10 miles underground, more than twice as deep as the 1990 quakes, and thus is probably less likely to be part of a cluster or cause damage, Oppenheimer said.
No comments:
Post a Comment