
Map showing the location
The 'Andaman Sea' (; ) is a body of water to the southeast of the
Bay of Bengal, south of
Myanmar, west of
Thailand and east of the
Andaman Islands; it is part of the
Indian Ocean. It is roughly 1200
kilometres long (north-south) and 650 kilometres wide (east-west), with an area of 797,700
km². Its average depth is 870
meters, and the maximum depth is 3,777 meters.
At its southeastern reaches, the Andaman Sea narrows to form the
Straits of Malacca, which separate the
Malay Peninsula from the island of
Sumatra.
Ocean floor tectonics
Running in a rough north-south line on the seabed of the Andaman Sea is the boundary between two
tectonic plates, the
Burma plate and the
Sunda Plate. These plates (or microplates) are believed to have formerly been part of the larger
Eurasian Plate, but were formed when
transform fault activity intensified as the
Indian Plate began its substantive collision with the Eurasian
continent.
As a result, a
seafloor spreading centre was created, which began to form the
marginal basin which would become the Andaman Sea, the current stages of which commenced approximately 3-4 million years ago (
Ma).
Volcanic activity
Within the sea to the east of the main
Great Andaman island group is
Barren Island, an
active volcano (the only presently active
volcano associated with the
Indian subcontinent). Its volcanic activity is due to the ongoing
subduction of the India Plate beneath the Andaman
island arc, which forces
magma to rise in this location of the Burma Plate. The volcanic island of
Narcondam which lies further to the north was also formed by this process; however it has not recently been active.
See also
★
Andaman Islands
★
Andaman and Nicobar Islands