A magnitude 4.0 earthquake hit near Parkfield at 3:40 p.m. Wednesday.
The quake was centered about 4 miles northwest of the town near the northeastern border of San Luis Obispo County, according to the U.S. Geological Survey.
The temblor was initially reported as a magnitude 4.3, but was later adjusted to 4.0.
People from across the county, including San Luis Obispo, Los Osos and Atascadero, reported feeling the jolt.
More at USGS.gov.