| Solomon Sea plate | |
|---|---|
 Approximate surface projections of active tectonic plates. Key: Solomon Sea plate, South Bismarck plate, Trobriand plate, Woodlark plate, Active trench subduction boundaries, Inactive trench subduction boundaries, current spreading boundary. TheAustralian plate to the southeast and thePacific plate to the northwest are not shown, but their complex collision has created these microplates. Click and then mouse over shows feature names. | |
| Type | Minor |
| Approximate area | 250,000 km2[1] |
| Movement1 | north |
| Speed1 | 86mm/year |
| Features | Pacific Ocean |
| 1Relative to theAfrican plate | |
TheSolomon Sea plate (also known as theSolomon plate[2]) is a minortectonic plate to the northwest of theSolomon Islands archipelago in the southPacific Ocean. It roughly corresponds with theSolomon Sea east ofPapua New Guinea. The plate boundaries are associated with high earthquake activity as part of theNew Britain subduction zone.
The tectonic regime in this part of the world is extremely complex and involves a number of minor as well as major plates. The Solomon Sea plate is anoceanic crustal plate remnant which is likely disappearing into threesubduction zones, to its north, east and west.[4] Its southeast margin runs along the Woodlark Rise, which extends into atransform fault called the Nubara Transform Fault marking the boundary with the adjoiningWoodlark plate.[4]
The northern subduction zone is located where the Solomon plate is diving below theSouth Bismarck plate to the northwest and thePacific plate to the northeast at theNew Britain Trench. This is area is extremely active seismologically.[5][6] The northwest part of the subduction zone is called theNew Britain Subduction Zone.New Britain inPapua New Guinea is the volcanic island formed from this collision and resulting volcanism. The complexities of its known geology, that of its island neighbour ofNew Ireland and the knownTabar,Lihir,Tanga andFeni Islands groups with undersaturated alkaline volcanics, some of which have been recently active, may not have resulted in a single accepted tectonic model to the north of the Solomon Sea plate that explains all observed features.[7][8]
The southwestern subduction zone is where the Solomon Sea plate has been diving below the formerIndo-Australian plate and has complexities still not fully resolved, but suggesting the possibility of a still activeTrobriand plate separating it from the presentAustralian plate.[4] If the Trobriand plate is presently fixed along the Solomon Sea plate's definite former subduction zone of the Trobriand Trough with the Solomon Sea plate, the Solomon Sea plate becomes quite a large microplate with much more complex tectonics. Accordingly, at this time more details on such tectonics are in the article on the Trobriand plate on the assumption that the Trobriand Trough is still an active subducting plate boundary.
