Tiny tremors and earthquakes provide intriguing clues about seismic activity

The black line is the interface between the Philippine and Eurasian tectonic plates, which gets deeper from right to left (towards the northwest). Black dots are conventional earthquakes, and red dots are tiny low-frequency earthquakes (LFEs), which were found in the high fluid pressure/transient slip zone where silent earthquakes likely form. Mapping out the LFEs could enable scientists to locate silent slips and thus provide an early warning of a potential major rupture on the adjacent locked section of the plate interface. Credit: David Shelly, Stanford University