The United States Geological Survey recorded a Magnitude 7.9 Earthquake at a depth of 136 km,beneath central Bougainville Island, Papua New Guinea, at about 2.30 pm local time (about 4.30 am GMT) on Saturday 22 January 2017. This is a large quake, and was felt across Bourgainville, as well as northern parts of the Solomon Islands, New Britain and mainland Papua New Guinea, and some damage to buildings has been reported on Bougainville.
The approximate location of the 22 January 2017 Bougainville Earthquake. USGS.
Bougainville Island lies on the southern fringe of the Pacific Plate. To the south of the island the Solomon Sea Plate is being subducted beneath the Pacific Plate along the Bougainville Trench, passing under the island of Bougainville as it sinks into the Earth. This is not a smooth process; the rocks of the two plates constantly stick together, then break apart as the pressure builds up, causing Earthquakes in the process.
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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