Monday 22 April 2019

Magnitude 6.1 Earthquake beneath Luzon Island kills at least eight.

The United States Geological Survey recorded a Magnitude 6.1 Earthquake at a depth of 20 km beneath central Luzon Island, the Philippines, slightly after 5.10 pm local time (slightly after 9.10 am GMT) on Monday 22 April 2019. The event is reported to have caused at least eight fatalities, with five people, including two children, killed in separate house collapses in the towns of Porac and Lubao Pampanga Province, and three more known to have died in a supermarket collapse in Porac, where about forty more are feared to be beneath the remains of the building (though some have been extracted alive).

Water from a roof-top swiming pool cascading down the side of the Anchor Skysuites building in Manila following a Magnitude 6.1 Earthquake on Luzon Island. Viral Press/YouTube.

The geology of the Philippines is complex, with the majority of the islands located on the east of the Sunda Plate. To the east of this lies the Philippine Sea plate, which is being subducted beneath the Sunda Plate (a breakaway part of the Eurasian Plate); further east, in the Mariana Islands, the Pacific Plate is being subducted beneath the Philippine Sea Plate. This is not a smooth process, and the rocks of the tectonic plates frequently stick together before eventually being broken apart by the rising pressure, leading to Earthquakes in the process.
 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.
See also...
Follow Sciency Thoughts on Facebook.