The Philippine Institute of Volcanology and Seismology recorded a Magnitude 5.7 Earthquake at a depth of 14 km slightly off the coast of Hinatuan in Surigao del Sur Province on Mindanao Island, Philippines, slightly before 2.10 pm local time (slightly before 6.10 am GMT) on Friday 31 July 2020. There are no reports of any damage or casualties associated with this event, but it was widely felt across eastern Mindanao.
The location of the 31 July 2020 Surigao del Sur Earthquake. USGS.
The geology of the central Philippines is Complex. The west of Mindanao Island is located on the Banda (or Sunda) Microplate, and the east on the Philippine Plate, which is being subducted beneath the Sunda (or Banda) Microplate along the central part of the island. Immediately to the east of the Island the Pacific Plate is being subducted along the Philippine Trench, and passes beneath eastern Mindanao as it sinks into the Earth. This is not a smooth process, an the plates constantly stick together then break apart again as the pressure builds up, resulting in Earthquakes.
Subduction beneath the Philippines. Yves Descatoire/Singapore Earth Observatory.
Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.
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