A preliminary magnitude-3.6 earthquake shook the Montecito area Sunday, according to the U.S. Geological Survey.
More than 500 people reported feeling the shaker in Santa Barbara, Goleta and beyond.
Residents as far as Lompoc also reported feeling the temblor.
There were no immediate reports of damage.
A preliminary magnitude-3.1 aftershock struck the same area a hour later.