Sunday’s earthquake occurred along the West Napa fault. But two others faults are close by, the Hayward Fault and the Rodgers Creek fault.
USGS scientist Fred Pollitz says scientists are keeping an eye on the Hayward Fault because it’s constantly accumulating stress.
But nearby Lake Berryessa could also be at risk. It had two large magnitude earthquakes in 1891.
“Given the proximity of Sunday’s earthquake to Lake Berryessa, that would certainly prompt us to focus attention on that area as well as other areas along the coast ranges that have active faults.”
Scientists say it is possible for drought to cause additional stress on faults.
But Pollitz says long term stress changes seem to be more responsible for triggering earthquakes.