(also Sunda Trench), a deep trench in the eastern part of the Indian Ocean. The Java Trench extends from the base of the continental slope of Burma (about 18°N lat.) along the underwater slopes of the Andaman, Nicobar, and Greater Sunda islands for a distance of about 2,900 km. The trench floor, which is narrow in the east, reaches a maximum depth of 7,130 m (7,209 m or 7,450 m according to soundings taken south of Java)—the greatest depth in the Indian Ocean. In the northern and central parts, the trench floor has a width of about 35 km and is leveled by a layer of sediment whose thickness reaches 3 km in the north. The sediments are terrigenous silts with a large admixture of volcanic material.