Did you feel Saturday’s NorCal quake? Here’s where it happened

A minor earthquake hit Contra Costa County on Saturday afternoon, with no injuries reported.

The U.S. Geological Survey reported a 3.8 magnitude earthquake at 1:29 p.m. Saturday near Blackhawk, southeast of Walnut Creek on the Interstate 680 corridor. Blackhawk is a master-planned community with a population of about 9,354, according to census figures.

The agency’s crowd-sourced analysis of the temblor found that 581 people in the Northern California area reported feeling the quake – as far away as Petaluma – but said it was “weak” or “light” in intensity.

A dispatcher for the Contra Costa Sheriff’s office, which serves Blackhawk, said the agency hadn’t received any calls for service related to the quake.

Anita Chabria: 916-321-1049, @chabriaa