The West Melanesian Trench (previously known as Manus Trench ) is an oceanic trench in the Bismarck Sea north of Papua New Guinea delineating the plate tectonic boundary between the Caroline and North Bismarck plates.
6-408: There is only slight seismic activity along both the trench, and its status as an active subduction zone, as proposed in the 2003 general model of major plate movement, is not generally accepted now. A relative motion of 1 cm/year (0.39 in/year) or less has, nevertheless, been suggested for the trench, roughly normal to the trench. The Kilinailau Trench east of New Ireland appears to form
12-801: A continuation to the south west and is thought to mark the boundary between the Pacific and North Bismarck plates. It is, however, disputed whether the Caroline Plate moves independently from the Pacific Plate. If not, the West Melanesian and Kilinailau trenches form the Pacific-North Bismarck boundary together. The area to the western end of the trench is actively subducting under the Australian Plate at
18-532: Is a stub . You can help Misplaced Pages by expanding it . Kilinailau Trench The Kilinailau Trench is an oceanic trench delineating the former oceanic crust boundary between the Pacific Plate and the now inactive North Bismarck Plate , in the area to the west of Papua New Guinea . To its south west is the inactive North Solomon Trench. The collision of the Ontong Java Plateau in
24-570: The New Guinea Trench . Perpendicular to the two trenches is another trench, the Mussau Trough separating the Caroline Plate and Pacific Plate. This areas tectonics is still poorly understood. 0°14′02″S 146°54′29″E / 0.23395233°S 146.9081862°E / -0.23395233; 146.9081862 This oceanography article is a stub . You can help Misplaced Pages by expanding it . This tectonics article
30-626: The Solomons. The Melanesian ocean arc ridge structures formed when the trench was active are to its west and would include the north eastern part of New Ireland . The West Melanesian Trench (Manus Trench) , which looks as if it is a western continuation of the Kilinailai Trench, marks the boundary between the Caroline Plate and North Bismarck Plates. It is, however, disputed whether the Caroline Plate moves independently from
36-473: The then subducting oceanic crust of the Pacific Plate, initially to the trench's south-east, changed the plate collision dynamics relative to the then Indo-Australian Plate to the west. Now the Ontong Java Plateau is just to the east of the trench and its great depth of crust appears to explain why subduction stalled here, and moved to the opposite direction along the far side of New Britain and
#953046