3.4 Aftershock Centered in Northridge

Six months to the day after the Northridge earthquake ravaged the Southland, a 3.4 magnitude aftershock rattled across the San Fernando Valley on Sunday morning. It caused no damage but was felt as far away as Santa Monica, seismologists said.

The aftershock, which hit at 8:29 a.m., was centered in Northridge a mile southeast of Chatsworth and was one of several hundred since the Jan. 17 quake, according to Caltech.

The aftershock was closer to the surface than some of the recent rumblings but follows what seismologists call a normal pattern after a large earthquake.

“We don’t really know how long they will go on,” said Russ Needham of the National Earthquake Information Center in Golden, Colo. “But I would think they would begin abating down to the point where they will be smaller.”

Sunday’s aftershock was the strongest in several weeks. On June 15, seismologists recorded a magnitude 4.2 quake, Needham said. There have been about 260 aftershocks between 3.0 and 3.9 since Jan. 17.