The Philippine Institute of Volcanology and Seismology
recorded a Magnitude 6.5 Earthquake at a depth of 8 km about 27 km to
the east of the town of Tulunan in Cotabato Province on Mindanao
Island, Philippines, slightly after 9.10 am local time (slightly after
1.10 am GMT) on Thursday 31 October 2019. The Earthquake is known to
have killed at least seven people and injured at least 11 more, with the event being felt across the southern Philippines. This is the third major Earthquake in the region within a month, with Earthquakes on the 16th and 29th of October having claimed seven and ten lives respectively.
Hotel in Kidapawan City, Cotabato, which partially collapsed following a Magnitude 6.5 Earthquake on 31 October 2019. Genghis Manero/Rappler.
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.
The
location of the 31 October 2019 Cotabato Province Earthquake. Contour
lines show rates of movement during the quake, the red line is a
boundary between two tectonic plates, in this case the Pacific and Philippine plates. USGS.
See also...
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