Major Quake On Hayward Fault Expected Any Day Warns USGS Scientist

Major earthquake on San Francisco's Hayward Fault expected 'any day now': 140-year wait has come to an end, claims geophysicist

major quake

A U.S. Geological Survey scientist has warned that the fault that produced a 4.1-magnitude earthquake in Fremont early Tuesday morning is expected to produce a major earthquake “any day now”.

The fault is due to trigger another ‘major earthquake’ as it is currently at the end of its 140-year cycle, claims Tom Brocher, a research geophysicist with the USGS.

Brocher also urged residents in the Bay area to take steps to prepare for a major earthquake.

Yesterdays quake happened along the Hayward fault, which has been dormant since its last quake in 1868

CBS Global reports: The quake caused some BART delays early Tuesday while work crews checked the tracks, but appears to have caused no major damage. At least 13 smaller quakes or aftershocks had been reported near the same location as of 6:42 a.m., the largest of which was a 2.7-magnitude at 2:56 a.m.

While damage from the quake was minimal, scientists warn that a much larger one is expected on the Hayward Fault, which extends from San Pablo Bay in the north to Fremont in the south and passes through heavily populated areas including Berkeley, Oakland, Hayward and Fremont.

The last big earthquake on the fault, estimated to have a 6.8-magnitude, occurred in 1868, according to the USGS.

It killed about 30 people and caused extensive property damage in the Bay Area, particularly in the city of Hayward, from which the fault derives its name. Until the larger 1906 earthquake, it was widely referred to as the “Great San Francisco Earthquake.”

“The population is now 100 times bigger in the East Bay, so we have many more people that will be impacted,” said Tom Brocher, a research geophysicist with the USGS.

“We keep a close eye on the Hayward Fault because it does sit in the heart of the Bay Area and when we do get a big earthquake on it, it’s going to have a big impact on the entire Bay Area,” Brocher said.

While a 2008 report put the probability of a 6.7-magnitude or larger earthquake on the Hayward-Rodgers Creek Fault system over the next 30 years at 31 percent, Brocher said the reality is a major quake is expected on the fault “any day now.”

“The past five major earthquakes on the fault have been about 140 years apart, and now we’re 147 years from that 1868 earthquake, so we definitely feel that could happen any time,” Brocher said.

Brocher urged residents to take steps to prepare for a major earthquake.