Using smart phones to crowdsource earthquake detection

Los Angeles Times : Even a few seconds’ warning of an impending earthquake could be enough to allow people to prepare. Although an earthquake early-warning system is already being designed for California, such systems have proven prohibitively expensive to build and maintain. Instead, Thomas Heaton of Caltech and his colleagues propose taking advantage of the ubiquitousness of smart phones and their GPS functionality to create a low-cost alternative. The system would use the ability of the phones’ internal accelerometers to detect movement. According to the researchers, the difficult part was distinguishing between actual earthquake activity and the day-to-day jostling a phone undergoes through normal use. They tested their system using data from the 2011 Tohoku earthquake and found that if at least 103 phones registered the same amount of surface displacement at the same time, it was likely an earthquake had occurred. Next the researchers plan to test their system under real-world conditions in Chile.