Draining aquifers probably triggered deadly 2011 tremor
Farmers and other residents pumping groundwater from Earth’s crust probably triggered an earthquake that killed nine people last year in southeastern Spain, scientists have found.
Sucking up water for decades would have unloaded stresses within the ground and hastened a quake that was likely to happen anyway, says Pablo González, a geologist at the University of Western Ontario in London, Canada.
“Even without the groundwater extraction, the earthquake was overdue,” he says. But human activities provided “a kind of triggering or controlling.”
González and his colleagues report the discovery online October 21 in Nature Geoscience.
Scientists know that people can change the rate of earthquakes by piling up water within the crust, such as behind a dam. Some researchers argue — though it is not entirely accepted — that filling a nearby reservoir may have set off the magnitude 7.9 quake that killed some 80