thumb|400px|Map showing earthquake activity in the vicinity of the Java Trench around the time of the 2004 Indian Ocean earthquake. Prepared by the United States Geological SurveyThe
Java Trench, more accurately called
Sunda Trench, located in the northeastern
Indian Ocean, with a length of and a maximum depth of (at 10°19'S, 109°58'E, about 320 km south of
Yogyakarta), is the deepest point in the
Indian Ocean. It stretches from the
Lesser Sunda Islands past
Java, around the southern coast of
Sumatra on to the
Andaman islands, about 300 km off the coasts of
Java and
Sumatra, and forms the boundary between
Indo-Australian Plate and
Eurasian plate, is part of the
Pacific Ring of Fire and a ring of
oceanic trenches around the northern edges of the
Australian Plate.
There is
scientific evidence that the recent
earthquake activity in the area of the Java Trench could lead to further catastrophic shifting within a relatively short period of time, perhaps less than a decade. This threat has resulted in international agreements to establish a
tsunami warning system in place along the
Indian Ocean coast.
Characteristics
For about half its length, off of
Sumatra, it is divided into two parallel troughs by an underwater ridge, and much of the trench is at least partially filled with sediments. Mappings after the
2004 Indian Ocean earthquake of the plate boundary showed resemblance to
suspension bridge cables, with peaks and sags, indicative of
asperity and locked faults, instead of the traditional wedge shape expected.
Exploration
Some of the earliest exploration of the Trench occurred in the late 1950s when
Robert Fisher, Research Geologist at the
Scripps Institution of Oceanography, investigated the trench as part of a world wide scientific field exploration of the world's ocean floor and sub-oceanic crustal-structure. Bomb-sounding, echo-train analysis and manometer were some of the techniques used to determine the depth of the trench. The research contributed to an understanding of the subduction characteristic of the Pacific margins.
Various agencies have explored the trench in the aftermath of the 2004 earthquake, and these explorations have revealed extensive changes in the ocean floor.
See also
