Aftershock: Magnitude 3.0 earthquake measured near Berkeley

BERKELEY, Calif. - A magnitude 3.0 earthquake in the East Bay was recorded by the U.S. Geological Survey at 6:21 p.m. on Monday. 

The quake was measured nearly 2 miles southeast of Berkeley in the Claremont neighborhood. 

This comes after a magnitude 4.3 earthquake, near the Claremont Hotel in Berkeley, jolted many out of bed overnight early Monday morning. 

There were some phone calls to KTVU from viewers who said they felt it. Staff at the station experienced the tectonic shift as well. 

A USGS scientist on KTVU's The 4 said there were already aftershocks measured at 2.3 and 2.6 after the initial middle-of-the-night temblor and that we could expect more. 

Robert De Groot with USGS and a coordinator for the Shake Alert Early Warning System, said the app worked effectively and as it was designed. He said aftershocks can go on for a while and that "there's about a 14% chance of magnitude 3.0 aftershock over the next week," De Groot said.

"If you're further out, say if you were out maybe out towards Antioch, south in Fremont, or parts of San Francisco, you may have got a second or two before the heavy shaking from the earthquake arrived. The Shake Alert system is very quick. But it's not so quick that it can always beat the earthquake waves," De Groot said. 

He said that the shaking feeling can be unsettling but reminded us that California is in earthquake country. This is a good reminder to be prepared with an earthquake supply kit, have your phone ready and learn more at shakealert.org.

Monday's earthquakes originated under the Hayward fault. 

"Some day…it's not a matter of if, it's a matter of when there will be a major event along the Hayward Fault," De Groot said.