The quake was reported by the U.S. Tsunami Warning System at 10:44 this morning.
The magnitude 7.0 earthquake rattled much of the coast of northern California and Southern Oregon. Centered about 45 miles southwest of Eureka, the quake triggered a tsunami warning that led coastal residents to run for higher ground. The tsunami warning was cancelled just before noon.
Many in the region received loud alerts on their cell phones through the U.S.G.S ShakeAlert early warning system. Officials say that at least half a million people got the alerts.
Officials reported little damage and the tsunami never materialized, though the utility PG& E reported nearly 10-thousand people lost power for a time.
California Governor Gavin Newsom issued an emergency declaration covering Humboldt, Mendocino and DelNorte counties to help with any needed recovery efforts.
Christine Goulet, with the U.S. Geological Survey’s Earthquake Science Center warned of likely aftershocks in the coming days.
"The general concept is that earthquakes are expected following a large one, such as a seven, that’s a major earthquake," she said. "They’ll decrease in intensity and what people feel and in frequency over time.”
Robert DeGroot, with the U.S. Geological Survey, described this area of northern California as “highly tectonically active.”
"This area is more generally known as the Mendocino Triple Junction. This is a place where the Cascadia Subduction Zone, the Mendocino Fault and the San Andreas Fault all come together," De Groot said in a briefing Thursday afternoon
The Cascadia subduction zone is a fault line of around 600 miles that stretches from the Northern California coast to Canada.
