Three quakes shake Contra Costa County

Three earthquakes struck Contra Costa County within the span of 15 minutes this afternoon, according to the U.S. Geological Survey.

The first earthquake recorded at 3:01 p.m. had a preliminary magnitude of 2.5 and had a depth of 8 miles, USGS officials said.

The quake was in an area 1 mile south of Concord, 2 miles northeast of Pleasant Hill and 4 miles north-northeast of Walnut Creek, USGS officials said.

A second temblor with a preliminary magnitude of 4.0 and a depth of 9 miles was recorded soon after at 3:13 p.m. in the same area as the first earthquake, according to the USGS.

The third quake occurred a minute later with a preliminary magnitude of 2.7 and a depth of 8.1 miles in the same region, USGS officials said.