Tectonic plates near Papua New Guinea

The northward-migrating Solomon Sea Plate is subducted under the South Bismarck Plate.
The Solomon Sea Plate is also subducted beneath the Pacific Plate.
There are two short spreading centers, one at the southeast margin of the Solomon Sea Plate and the other at the north edge of the South Bismarck Plate.
As can be seen from the map below, the Woodlark Plate stretches under the North-Eastern Coast of Papua New Guinea. Powerful earthquakes and volcanoes result from the subduction of these plates.

Arrows show net plate motion relative to the Australian Plate.

Courtesy Oregon State University.
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