GPS data can detect early signs of megaquakes

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Scientists have discovered a way to identify indicators of a mega earthquake using GPS-based information, an advance that may help improve early warning systems for quakes. The researchers from University of Oregon in the US combed through databases of earthquakes since the early 1990s have discovered a possible defining moment 10-15 seconds into an event that could signal a magnitude seven or larger quake.Likewise, that moment — gleaned from GPS data on the peak rate of acceleration of ground displacement — can indicate a smaller event. GPS picks up an initial signal of movement along a fault similar to a seismometer detecting the smallest first moments of an earthquake.