WALNUT CREEK -- A magnitude 2.4 earthquake occurred in central Contra Costa this morning, the U.S. Geological Survey reported.

The temblor, described as a microquake because its magnitude was less than 3, occurred at 8:48 a.m. and was centered near the intersection of Ygnacio Valley and Oak Grove roads in Walnut Creek.

The quake yielded no reports of injuries or damage, according to local emergency agencies.