Lathrop Rattled By 3.1 Magnitude Earthquake
Folks in Lathrop had a wake-up call from Mother Earth this morning, when a magnitude 3.1 earthquake struck San Joaquin County.

Quakes don't often strike in San Joaquin County, but they aren't unheard of either, "There are active faults everywhere you look in California, including the Central Valley," says Kurtis Burmeister, a geologist at the University of the Pacific.

The same sediments that make the Delta so fertile, also make it ripe for dangerous shaking.

"The Delta region has for millions of years been a collecting point for all of the rivers flowing out of the Central Valley, as such this region is underlain by a lot of water saturated sediments- sands and mud - that when shaken up enough -- will cause those materials to liquefy," Burmeister told FOX40. Liquefaction is what happened to San Francisco's Marina district during the 1989 Loma Prieta earthquake.

Large quakes have struck the Delta in the past, in the mid-1800's there was a 6.6 quake that struck outside of modern-day Vacaville.

According to the U.S. Geological Survey, this morning's 4 a.m. quake is cousin to a 3.7 shaker in 2002 in Rio Vista.