4.0 sharp jolt felt around the Bay

ALAMO, CA Another aftershock of 1.3 hit 3 miles from Alamo hit at 9:48 p.m. This was the second aftershock felt after the initial 4.0 quake. The first aftershock of 1.9 hit at 9:05 p.m. 5 miles north-northeast of Blackhawk. The light quake appears to have hit close to the Calaveras Fault.

The U.S. Geological Survey is reporting an earthquake with a preliminary magnitude of 4.0 struck at 9 p.m. today near Danville.

According to the USGS, the earthquake had a depth of 10.1 miles and was centered 4 miles north northwest of Danville and 7 miles south of Concord.

As a result of an earthquake centered near Danville with a U.S. Geological Survey preliminary magnitude of 4.0, Bay Area Rapid Transit trains were temporarily stopped.

"We are stopping all of our trains for five minutes. It's part of our normal procedure," said BART spokesman Linton Johnson.

The earthquake struck at 9 p.m. and had a depth of about 10 miles. The quake was centered 4 miles north northwest of Danville and 7 miles south of Concord.

BART stops its trains after an earthquake in case of a larger quake following the initial one or in case of aftershocks, Johnson said.

Trains were moving once again after the temporary stop but were moving at a slower speed than usual, said Johnson, who added that there have been no reports of structural damage.

There was one small aftershock with a magnitude of 1.9 just five minutes after the first one that was centered nearby.

Johnson said BART trains were expected to be back on schedule after delays of 10 to 15 minutes by about 9:45 p.m.

There are no reports yet of any major damage.

Bay City News contributed to this report.