EL CENTRO, Calif. — The California-Mexico border was rattled by a magnitude 4.5 aftershock Tuesday of a major earthquake that hit the region April 4. No damage was immediately reported.
The U.S. Geological Survey said the quake struck at 5:38 p.m. and was centered 18 miles west-southwest of El Centro.
USGS computers initially calculated the quake’s magnitude at 5.1, but seismologists downgraded it hours later.
The aftershock was centered about 40 miles northwest of the magnitude-7.2 quake that struck on Easter Sunday in northern Baja California, Mexico, said Susan Potter, a geophysicist at the National Earthquake Information Center in Golden.
“The 7.2 quake was shallow and large, so we’d expect to see aftershocks for quite some time,” she said.
Tuesday’s quake was felt at San Diego’s Petco Park, home of the San Diego Padres.
