A 4.5 magnitude quake with an epicenter east of Berkeley shook the San Francisco bay area at 2:39 a.m. early Thursday morning.
"The real question is: is this a foreshock to something larger?"
The Hayward Fault is capable of producing a 7-magnitude fault, which would have caused significantly more damage.
The quake was on the Hayward Fault, part of the San Andreas Fault.
The natural disaster hit the San Francisco area about 2.40am local time (11.40pm NZT) and lasted about 10 seconds, causing a "little bit of rolling motion and a sharp jolt", NBC Bay Area Chief Meteorologist Jeff Ranieri wrote on Twitter. Let us know on our Facebook page here.
The epicenter was in Berkeley just across the bay from San Francisco
At a Safeway in San Leandro, one person reported that the natural disaster had knocked down a ceiling panel and also shaken some items from the grocery store shelves. A 2003 report determined that the Hayward-Rodgers Creek fault system would produce at least a magnitude 6.7 quake in the next 30 years. But a video posted to Twitter showed products that had fallen from the shelves of a San Leandro Safeway store.
He told the Chronicle that by 4:15 a.m., there had been no aftershocks, which he called "a good sign".
Transit agencies reported there were delays during the early morning commute while they checked for any damage. An estimated 9 million people have felt the rumblings of the natural disaster that hit around 2.39 AM in the early morning.
"HOLY COW! I'm in the Richmond District-SF, and it felt like a 5.5!", she wrote. "I thought my wall of bookcases would fall down". The event was felt as far east as Sacramento and beyond San Jose, to the south of Berkeley.
"Woke us up in Alameda", posted Gonsalves while Walls posted: "In Novato and jolted me awake while my bed was rocking".
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