COBB, Calif. – A quake that followed a larger 4.5-magnitude earthquake early Saturday, May 5, has been upgraded in size.

The U.S. Geological Survey reported Monday evening that an earthquake it originally had reported as 2.3 in magnitude – occurring just a minute after the 4.5 magnitude quake Saturday – was in fact a 3.3.

The 4.5-magnitude temblor was centered three miles east of The Geysers geothermal steamfield and three miles southwest of Cobb, the U.S. Geological Survey reported.

The 3.3-magnitude quake that followed – the largest of numerous aftershocks – was centered two miles east of The Geysers and four miles southwest of Cobb, according to the agency's report.

The larger quake elicited 220 shake reports from 46 zip codes, but as of Monday evening the U.S. Geological Survey had not received shake reports on the 3.3-magnitude quake.

Email Elizabeth Larson at This email address is being protected from spambots. You need JavaScript enabled to view it. .