Three earthquakes of 2.5 magnitude and higher hit near Pacifica in quick succession between 2:2:34 p.m. and 2:47 p.m. on Saturday according to data supplied by the United States Geological Survey.
The first quake, at 2.6, hit about a mile northeast of Pacifica at 2:34:52. The second one, the strongest at 2.8, hit 16 seconds later about two miles southwest of Pacifica.
A third earthquake was centered about two miles north of Montara at 2:47:34 and was recoded at 2.5.
The first earthquake was 3.4 miles underground, while the other two were about 5.5 miles underground.
No injuries or damage have been reported.
There have been 10 earthquakes of 2.5 or higher recorded in California over the past seven days, and about 200 around the world.