SAN FRANCISCO (KRON) — Some Bay Area residents are reporting feeling a big earthquake off the shore of Humboldt County.

Preliminary reports from the U.S. Geological Survey say it was a 6.2 magnitude quake, reported around 12:10 p.m. on Monday.

It was about 45 miles from Eureka, and about 24 miles from Petrolia.

According to the California Geological Survey, the earthquake map shows that there have been 59 earthquakes in the area on Monday. They say the largest aftershock was measured at 4.5 magnitude.

“This aftershock behavior is not unusual and is a good reminder that, if you feel shaking to “Drop, Cover and Hold On,” the geological survey said in a Twitter post.

A San Francisco resident called into KRON4 and said they felt it in the inner Sunset, near UCSF. A KRON4 employee said they felt it in Emeryville.