Central Coast Hit by Quake

One of the strongest aftershocks of the Dec. 22 San Simeon earthquake struck the Central Coast on Wednesday, rocking a wide area from Monterey to the Santa Ynez Valley.

The U.S. Geological Survey said the quake measured a magnitude 4.5 and its epicenter was nine miles northeast of San Simeon and 23 miles northwest of Paso Robles. In December’s quake, which had a magnitude of 6.5, two women were killed in Paso Robles and the town was heavily damaged.

There were no immediate reports of damage from Wednesday’s aftershock, which was the strongest since a magnitude 4.6 occurred on Christmas Day.

Jean Hardebeck, a scientist with the Geological Survey in Menlo Park, said the aftershock was the 17th to have a magnitude of at least 4.0.

There have been more than 4,000 aftershocks in all.

Within an hour of the aftershock, about 400 people reported on the Geological Survey’s “Did you feel it?” website that they had detected ground motion from the quake.

Their descriptions indicated that the aftershock had registered about a 5 on the Modified Mercalli scale in Paso Robles and had been felt more lightly in San Luis Obispo.

A quake of 5 on the Mercalli scale indicates that the quake was widely felt outdoors, woke people who were sleeping, spilled some liquids, upset small objects, swung doors open and changed the rate of pendulums in clocks.

Aftershocks can continue for months or even years after an initial quake of a magnitude 6.5.

The original San Simeon quake caused an estimated $250-million damage.