A magnitude 4.4 earthquake centered in the San Gabriel Valley rattled a sizable chunk of Southern California Tuesday evening, the U.S. Geological Survey said.

It struck at 7:33 p.m. about 2.5 miles north of La Verne at a depth of 3.79 miles, according to the agency.

That depth — relatively shallow — is what allowed the quake to be felt across the region, according to earthquake expert Lucy Jones.

“People who were very near it would have had strong shaking, potentially even throwing a few things off of shelves,” Jones said during a briefing at the Caltech Seismological Laboratory. “As you get farther away, the shaking gets lower and more rolling motion.”

It was felt as far as the Santa Clarita Valley, Victorville and Riverside.

Scientists at Caltech were alerted to the quake three second before it hit thanks to its early warning system……more here