The third temblor, a magnitude 3.3, was cenetered about 2 miles north of the East San Jose foothills, the USGS said. The first quake, a magnitude-3.3, occurred at 10:32 a.m. Its epicenter was less than 2 miles north of the eastern foothills of San Jose, 3 miles northeast of Alum Rock and 5.1 miles southeast from Milpitas, the USGS reported.
Another quake, a magnitude-2.6, was felt in the same area around 12:30 p.m. All of the earthquakes occurred on the Hayward Fault, the USGS said. There's nothing unusual about the quakes, the agency said, even though all five were in the same area. "They're good kind of earthquakes to have," geophysicist Brian Kilgore said. "They're large enough to be felt but not so large to cause damage. They are a terrific reminder to think about your personal earthquake plan."
Locations where people experienced the earthquake include the Matrix Casino, 8x8, Inc. and Cisco headquarters, Vinci Park Elementary School and the Evergreens area of San Jose. Tremors were felt as far away as Sunnyvale, where Marianne Bettio's "computer monitor shook on the desk," and in Milpitas. The USGS said it's nearly impossible to tell if a quake is a foreshock before a bigger earthquake but added that foreshocks are very rare.