San Francisco quake sparks fears of a larger one on the way

Residents of San Francisco and the Bay Area had quite the wake-up call at 2:39 am Thursday morning when a 4.4 magnitude earthquake was felt by millions in the region.

Luckily, so far no injuries or serious building damage been reported, and San Francisco’s Department of Emergency Management texted that there was no tsunami warning.

The US Geological Survey (USGS) reported that the epicenter of the quake was located in Berkeley, California occurring at a depth of about eight miles into the earth.

The USGS also said the quake was the result of movement along the Hayward Fault, which is connected to the San Andreas fault system.

The Hayward fault has many geologists and seismologists concerned because it’s overdue for a larger quake, which typically occurs every 160 years. It’s been 150 years since the last major event.

The fault location and its connection to the San Andreas fault system mean that a major quake could result in significant devastation. The Hayward Fault is directly below millions of people and city buildings.

The USGS calls the fault “a tectonic time bomb.”

The 4.4 quake was classified as moderate and was fairly tame, rattling windows and shaking store shelves but the shaking was felt for miles. The LA Times even reported that people up to 150 miles away felt movement.

The USGS reports that there is a slight chance that this quake could be a precursor to a larger event on the way (five to ten percent) and that Bay Area residents should be wary of aftershocks.

Aftershocks can happen weeks after the initial quake, and people in Berkeley and San Francisco area are being asked to go over earthquake preparedness and stay alert.

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By Kay Vandette, Earth.com Staff Writer