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
Puerto Rico Trench assigned to genus "Peniagone". The other individual, a small crustacean, is tentatively identified as a "munnposid" "isopod", based on morphology and similar walking and jumping movements observed for other hadal "munnopsid" "isopods". Because these individual were not collected, it is not possible to obtain species-level identifications. However, these sightings likely exceed the deepest known records for genus "Peniagone" and family "Munnopsidae". Puerto Rico Trench The Puerto Rico Trench is located on the boundary between the Caribbean Sea and the Atlantic Ocean. The oceanic trench is associated with a complex transition between the Lesser Antilles subduction zone to the south and