The tremor was centered about 7.7 miles east of Blackhawk and 8.2 miles north of Livermore, according to the agency, which said it occurred around 1:11 p.m.
A 3.5 magnitude earthquake hit the same area about 13 minutes later, the USGS said. A day before, a 3.3 magnitude earthquake hit the South Bay, the NBC affiliate noted.
On social media, people reported feeling the tremor.
‘Big One’
After a large earthquake hit Southern California earlier in July, officials have warned about the “big one” hitting the state.“It is a wake-up call for the rest of the state and other parts of the nation, frankly,” Newsom said at a news conference on efforts to help a desert region jolted by back-to-back quakes.
A magnitude 6.4 earthquake July 4 and a magnitude 7.1 quake July 5 were centered 11 miles from the small town of Ridgecrest, about 150 miles from Los Angeles.
“Any time that we can go through a 7-point earthquake and we do not report a fatality, a major injury, do not suffer structure damage that was significant, I want to say that that was a blessing and a miracle,” Kern County Fire Department spokesman Andrew Freeborn said July 7.