Earthquakes have recently struck Alaska and Southern California
California was hit with two earthquakes this week, both ranking "moderate" on the Richter scale. Above: Damage from past earthquakes in Southern California. Creative Common

California was struck with two earthquakes and multiple aftershock effects, the first quake hitting the Greenville area late Thursday, the second, early Friday morning. According to U.S. Geological Survey, the more severe quake ranked a 5.7 on the Richter scale, the second ranking a reported 4.9. No injuries and minimal damage have been reported.

According to a report from the Northern California Seismic Network, that first quake hit at 8:47 p.m. Thursday night, with a recorded 5.69 magnitude; the quake is being classified as "moderate." Warnings for 5.0 magnitude or potentially large aftershocks were followed by reports of a dozen aftershocks, ranging in magnitude up to 3.5, the Los Angeles Times reports.

The earthquake was felt in various parts of the state, including Sacramento, Lodi, South Reno, Lake Tahoe, Susanville and Chico, with more than 7,000 residents having felt the quake. Some out-of-state residents in Oregon and Nevada also said they felt the quakes, the Huffington Post reports.

“People in the area felt a strong jolt, but it was not enough to generate serious damage, based on early field reports,” said geophysicist Radael Abreu.

The second quake hit the area early Friday morning, 114 miles north of Sacramento, ranking a 4.9 on the Richter scale. While it has yet to be reviewed by a seismologist, according to witnesses, the quake wasn’t severe.

The Northern California Seismic Network released a warning on Thursday that the area has a five to 10 percent chance of experiencing an equal or larger earthquake in the next week, as well as an additional 10 to 30 moderately strong aftershocks to follow.