Why earthquake predictions are usually wrong
Each year, on the third Thursday in October, millions of Americans participate in the largest earthquake drill on earth: The Great Shake Out.
It was created by a group at the Southern California Earthquake Center, which included Ms Jones.
During the drill, people practise the guidance of Drop, Cover, and Hold On: they drop to their knees, take cover under a sturdy object like a desk, and hold on for one minute.
The drill has become so popular since its inception that it has spread up the earthquake-prone coast to other states and countries.
If outdoors, people are advised to get to an open space away from trees, buildings or power-lines. Near the ocean, people practise fleeing to higher ground after the shaking stops to prepare for the possibility of a tsunami.
"Now, while the ground is not shaking, while it's not a very stressful situation, is really the best time to practise," said Brian Terbush, the Earthquake and Volcano Program Manager for the Washington state Emergency Management Division.
Apart from the drills, residents of West Coast states use a phone alert system maintained by USGS called ShakeAlert.
The system works by detecting pressure waves emitted by an earthquake. While it can't predict when an earthquake will happen in the distant future, it does give seconds of warning that could be life-saving. It is the closest thing to an earthquake "predictor" that has been invented so far.
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