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
Bentley Subglacial Trench Bentley Subglacial Trench The Bentley Subglacial Trench is a vast topographic trench in Marie Byrd Land, West Antarctica, 80°S, 115°W. At 2,555 meters (8,382 ft) below sea level, it (along with the deepest points within the adjacent Byrd Subglacial Basin) is among the lowest points on the surface of the Earth not covered by ocean, although it is covered by ice. (See Extremes on Earth and Vestfold Hills). The trench was named in 1961 after Charles R. Bentley who was the geophysicist in charge of the scientific expeditions in West Antarctica in 1957–59 that led to its discovery. Starting in