Java and Bali to the east. Borneo lies to the north and Christmas Island is to the south. It is the world's 13th largest island. Java is surrounded by the Java Sea to the north, Sunda Strait to the west, the Indian Ocean to the south and Bali Strait and Madura Strait in the east. Java is almost entirely of volcanic origin; it contains thirty-eight mountains forming an east–west spine that have at one time or another been active volcanoes. The highest volcano in Java is Mount Semeru (). The most active volcano in Java and also in Indonesia is Mount
Hikurangi Trench Hikurangi Trench The Hikurangi Trench, also called the Hikurangi Trough, is an oceanic trench in the bed of the Pacific Ocean off the east coast of the North Island of New Zealand, lying between the southern end of the Cook Strait and the Chatham Rise. It is the southward continuation of the much deeper Kermadec Trench. It lies in the Hikurangi Margin subduction zone, which is the southern extension of the Kermadec-Tonga subduction zone. The Hikurangi Margin is the subduction zone where the thick oceanic Hikurangi Plateau is subducting beneath continental crust of the Indo-Australian Plate. By contrast, the Kermadec