GPS Data: A Promising Early Warning System for Earthquakes

A global analysis of GPS time-series data from nearly 100 large earthquakes suggests the existence of a precursory phase of fault slip that occurs approximately two hours before seismic rupture. However, the current monitoring tools lack the necessary coverage and precision to detect or monitor for precursory slip at the scale of individual earthquakes, posing a significant challenge for practical earthquake prediction. If confirmed and reliably measured, this precursory phase could potentially provide a warning for large earthquakes.