"Nearly 40 small aftershocks struck on the Calaveras Fault on Wednesday, following Tuesday night's moderate earthquake near San Jose that startled residents throughout the Bay Area.
The 5.6-magnitude quake caused only minor damage in South Bay communities, and the aftershocks - the largest at 3:54 p.m. with a magnitude of 3.7 - occurred south of the main quake's epicenter near the Calaveras Reservoir, according to Tom Brocher, a seismologist with the U.S. Geological Survey in Menlo Park."
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/11/01/BACAT43ST.DTL
The 5.6-magnitude quake caused only minor damage in South Bay communities, and the aftershocks - the largest at 3:54 p.m. with a magnitude of 3.7 - occurred south of the main quake's epicenter near the Calaveras Reservoir, according to Tom Brocher, a seismologist with the U.S. Geological Survey in Menlo Park."
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/11/01/BACAT43ST.DTL