Sumatra Trench Sumatra Trench The Sumatra Trench belongs to the Sunda Trench or Java Trench. The Sunda subduction zone (called also: the Sumatra-Andaman subduction zone) is located in the east part of Indian Ocean, and is about 300 km from the southwest coast of Sumatra and Java islands. It extends over 5000 km long, starting from Burma in the northwest and ending at Sumba Island in the southeast. The Java trench was generated by the oblique subduction of the Indo-Australian Plate into the Sunda plate at a rate of 61mm/y (in the south) and 51mm/y (in the north). The oceanic crust being
Ontong Java Plateau Ontong Java Plateau The Ontong Java Plateau (OJP) is a huge oceanic plateau located in the south-west Pacific Ocean, north of the Solomon Islands. The OJP was emplaced 120 Ma with a much smaller volcanic event 90 Ma. Two other south-west Pacific plateaus, Manihiki and Hikurangi, now separated from the OJP by Cretaceous ocean basins, are of similar age and composition and probably formed as a single plateau and a contiguous large igneous province together with the OJP. When emplaced this Ontong Java-Manihiki-Hikurangi plateau covered 1% of Earth's surface and represented a volume of of basaltic magma. This "Ontong Java