The United States Geological Survey recorded a Magnitude 5.6 Earthquake at a depth of 10.0 km a little over 30 km to the north of Great Andaman Island, slightly before 3.10 am local time (slightly before 0.40 am GMT) on Wednesday 22 May 2018. There are no reports of any damage or injuries associated with this event, though people have reported feeling in in Port Blair, the capitol of the Andaman and Nicobar Islands, which is around 250 km to the south of the Earthquake's epicentre.
The approximate location of the 22 May 2019 Nicobar Islands Earthquake. USGS.
The Nicobar Islands sit on the Burma (or Burmese) Plate, a small tectonic plate which underlies part of the eastern Indian Ocean and the western part of Sumatra. To the west of the Nicobar Islands this plate is being subducted beneath the Indian Plate, but to the east the situation is more complex. The Burma Plate is being pushed northward relative to the Eurasia and the Sunda Plate (which underlies eastern Sumatra, Java, southern Southeast Asia, most of Borneo and the western Philippines) by the northward movement of the Indian Plate. There is also an area of seafloor spreading beneath the Andaman Sea (separating the Andaman and Nicobar Islands from Southeast Asia), which in turn causes stresses within the Burma Plate, leading to a zone of faulting upon which the Andaman and Nicobar Islands are situated.
(Left) The movement of the Burma and surrounding plates. Sheth et al. (2011.(Right) Tectonic stresses within and around the Burma Plate. Renjith (2013).
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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