(KRON) — A series of six earthquakes rattled in the East Bay Friday evening, according to the United States Geological Survey (USGS). A preliminary 2.5-magnitude earthquake was first reported near San Ramon at around 7:41 p.m., the USGS confirmed. Then five more quakes, one 2.9 magnitude, one 3.8-magnitude, one 4.0 magnitude, one 3.1 magnitude and another 2.9 magnitude all followed within 20 minutes. Park officials looking for people caught on camera throwing rocks at elephant seal Photo courtesy of US Geological Survey The deepest earthquake was listed to be 9.9 kilometers (or 6.15 miles), according to the USGS. The earthquakes were felt in Dublin, Danville and other parts of the East Bay. "In the San Ramon area specifically, we tend to see these little swells of a whole lot of little magnitude earthquakes — all about the same magnitude happening one after another — and then these swells happen quite frequently in time," said USGS geophysicist Dr. Sara Minson in an interview with KRON4's Dan Thorn. BART passengers should expect residual delays of up to 20 minutes due to the earthquakes, BART wrote in a social media post. These are the latest in a swarm of earthquakes clustered in the area. 11 minor earthquakes were registered on Dec. 8 in the valley. ...read more read less