Low-pitched, rumbling rocks could help predict when earthquakes strike, research says

TEPIC, MEXICO – Rocks under increasing pressure before earthquakes strike send out low-pitched rumbling sounds that the human ear cannot detect but could be used to predict when a tremor will strike, scientists said Monday. Researchers recreated powerful earthquake forces in a laboratory and used high-tech algorithms to pick out the acoustic clues amid all the other noise of a pending quake, according to findings published in Geophysical Research Letters, a journal published by the American Geophysical Union. The sounds are emitted typically a week before an earthquake occurs, so deciphering them would allow scientists to pinpoint the timing of a tremor, the research paper said. Scientists currently can calculate the probability of an earthquake in a particular area but not when it will happen, according to the U.S. Geological Survey. "People have said you can't predict earthquakes. We're now saying we believe for the first time we can predict an earthquake in a laboratory," said Colin Humphreys, professor of materials science at Cambridge University and one of the paper's authors.