The Big One more likely, earthquake forecast indicates

Researchers with the U.S. Geological Survey and other organizations said in a study released this week the estimated risk of a magnitude-8 or larger earthquake in the next 30 years has increased to 7%, up from 4.7% in the previous assessment in 2008.

Meanwhile, they said they now expect moderate-sized earthquakes of magnitudes from 6.5 to 7.5 to be somewhat less frequent than they had previously forecast. Earthquakes of magnitude 6.7 or larger — the size of the 1994 Northridge quake — are projected to strike once every 6.3 years, they said, down from once every 4.8 years.

Ned Field, a USGS geophysicist and lead author of the study, said the new forecast was created using a model that incorporates the latest research and seismological data.