HOLLISTER (CBS SF) — Two earthquakes registering a preliminary magnitude of 3.5 and 3.0 struck east of Gilroy, near Hollister Friday at 4:32 p.m. and 2:44 p.m. respectively, according to the U.S. Geological Survey’s automated seismograph alert network.
Both quakes struck at an estimated depth of just about 4 miles, below the earth’s surface, making this a very shallow quake.
Deeper quakes are less noticeable while a shallow quake–in the 0 to 40 mile depth range–can feel much stronger than their actual reported magnitude. Quakes just below the earth’s surface, in the 0 to 10 miles range, can cause even more damage at lower magnitudes.
COMPLETE QUAKE COVERAGE: CBS Earthquake Resource Center
Strong earthquakes with an epicenter off the coast can trigger tsunamis, depending on the size and type of the fault movement. The Pacific Tsunami Warning Center tracks earthquake data for the West Coast.
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