Chagos-Laccadive Ridge
Encyclopedia
Oceanic plateau
An oceanic plateau is a large, relatively flat submarine region that rises well above the level of the ambient seabed. While many oceanic plateaus are composed of continental crust, and often form a step interrupting the continental slope, some plateaus are undersea remnants of large igneous...
extending between the Northern and the Central Indian Ocean
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
.
The CLR extends northward for approximately 2350 km from 9° S at the southern end of the Chagos Archipelago
Chagos Archipelago
The Chagos Archipelago , is a group of seven atolls comprising more than 60 individual tropical islands in the Indian Ocean; situated some due south of the Maldives archipelago. This chain of islands are the southernmost archipelago of the Chagos-Laccadive Ridge a long submarine mountain range...
to 14° north around the Adas Bank
Adas Bank
Adas Bank is a submerged bank located off the west coast of India, between Angria Bank and Cora Divh bank of the Laccadive Islands . The closest coast of land is the Indian mainland close to Goa, which is 180 km ENE of Adas Bank...
. The islands of Chagos, the Maldives
Maldives
The Maldives , , officially Republic of Maldives , also referred to as the Maldive Islands, is an island nation in the Indian Ocean formed by a double chain of twenty-six atolls oriented north-south off India's Lakshadweep islands, between Minicoy Island and...
and the Lakshadweep
Lakshadweep
Lakshadweep , formerly known as the Laccadive, Minicoy, and Amindivi Islands, is a group of islands in the Laccadive Sea, 200 to 440 km off the coast of the South West Indian state of Kerala...
are the above-water parts of the Chagos-Laccadive Ridge.
The vast Chagos-Laccadive Ridge was formed by the Réunion volcanic hotspot
Réunion hotspot
The Réunion hotspot is a volcanic hotspot which currently lies under the Island of Réunion in the Indian Ocean. The Chagos-Laccadive Ridge and the southern part of the Mascarene Plateau are volcanic traces of the Réunion hotspot....
along with the southern part of the Mascarene Plateau
Mascarene Plateau
The Mascarene Plateau is an submarine plateau in the Indian Ocean, north and east of Madagascar. The plateau extends approximately 2000 km, from the Seychelles in the north to Réunion in the south. The plateau covers an area of over 115,000 km² of shallow water, with depths ranging from...
. Both plateaux are volcanic traces of the Réunion hotspot.
Although the Chagos-Laccadive Ridge is an aseismic ridge, between 1965 and 1970 an unusual, isolated swarm of earthquake
Earthquake
An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time...
s occurred on the west side of the Great Chagos Bank
Great Chagos Bank
The Great Chagos Bank, in the Chagos Archipelago, about South of the Maldives, is the largest atoll structure in the world, with a total area of . The Atoll is administered by the UK through the BIOT.-Islands:...
at approximately 6°00′S 71°20′E.