The Indonesian Baden Meteorologi, Klimatologie, dan Geophysica (Meteorological, Climatological and Geophysical Agency) recorded a Magnitude 6.2 Earthquake at a depth of 11 km off the north coast of Morotai Island in the Halmahera Islands, slightly after 10.30 pm local time (slightly after 1.30 pm GMT) on Tuesday 19 November 2013. There are no reports of any damage or casualties, but this was a large quake and is likely to have been felt across the island.
The approximate location of the 19 November 2013 Morotai Island Earthquake. Google Maps.
The Halmahera Islands arc a volcanic arc; formed where one tectonic plate is being subducted beneath another, with the underlying plate being melted by the heat of the Earth's interior, and lighter minerals bubbling up through the overlying plate to form volcanoes. However the Halmahera Islands are unusual in that they lie on a double subduction zone. The underlying plate, a northeaster extension of the Molucca Sea Plate, is being overridden form the Philippine Plate from the east and the Eurasian Plate from the west. The Halmahera volcanoes are located where the Philippine Plate is overriding the Molucca Sea Plate; to the west the Sangihe Islands lie where the Molucca Sea Plate is being overridden by the Eurasian Plate.
Sea also Magnitude 5.7 Earthquake of the north coast of Sulawesi, Explosive eruption on Mount Lokon, Eruption on Gamalama, Earthquake hits Sulawesi and Volcanic activity in the Halmahera Islands.
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