East Java also decided to join Indonesia. East Java province borders the Java Sea in the north, the Strait of Bali in the east, the Indian Ocean in the south, as well as the Central Java province in the west. The length of the east-west stretch of about 400 km. The width of the stretch of the north-south in the west about 200 km, but in the eastern part of narrower by about 60 km. Madura is the largest island in East Java, separated from the mainland Java by the Strait of Madura. Bawean Island is located about 150 km north of
Japan Trench earthquakes within the deeper part of the plate interface zone. No earthquakes have been observed or reported from the shallow aseismic zone of the north Japan Trench. Regions of rough ocean bottom subduction are correlated with large normal faulting earthquakes within the outer-rise region, along with larger tsunami earthquakes occurring at the shallow region of the plate interface (megathrust events) . In 1980, lipids samples were taken via sediment cores located on both the landward and distal sides of the Japan Trench during six sections of the Deep Sea Drilling Project's transect. They were analyzed using gas chromatography and computerized-gas