India has a total of 247 islands (distant islands) of which 204 lie in the Bay of Bengal and remaining in the Arabian Sea. The Bay islands consisting of Andaman and Nicobar group of islands have a crescendo shape and denote the peaks of submerged Tertiary mountain ranges-a continuation of the Arakan Yoma fold axis.
Their surface is covered with thick tropical forests. The Arabian Sea islands have a coral origin and are surrounded by fringing reefs (over the volcanic peaks). Besides there are a number of off shore islands along the Ganga-mouth, eastern and western coasts and in the Gulf of Mannar.
1.Arabian sea groups
2.Bay of Bengal group
Arabian sea groups
The islands of the Arabian sea include Lakshadweep and Minicoy. These are scattered between 8°N-12°N and 71°E -74°E longitude. These islands are located at a distance of
280 km-480 km off the Kerala coast. The entire island group is built of coral deposits. There are approximately 36 islands of which 11 are inhabited. Minicoy is the largest island with an area of 453 sq. km. The entire group of islands is broadly divided by the Eleventh degree channel, north of which is the Amini Island and to the south of the Canannore Island. The Islands of this archipelago have storm beaches consisting of unconsolidated pebbles, shingles, cobbles and boulders on the eastern seaboard.
The coastal line has some coral deposits, and beautiful beaches. These islands receive convectional rainfall and have an equatorial type of vegetation.
Bay of Bengal group
The Bay of Bengal island groups consist of about 572 islands/islets. These are situated roughly between 6°N-14°N and 92°E -94°E. The two principal groups of islets include the Ritchie’s archipelago and the Labrynth island. The entire group of island is divided into two broad categories – the Andaman in the north and the Nicobar in the south. They are separated by a water body which is called the Ten degree channel. It is believed that these islands are an elevated portion of submarine mountains. However, some smaller islands are volcanic in origin. Barren island, the only active volcano in India is also situated in the Nicobar islands.
The Andaman Group of Islands includes 204 islands the major among them being the Great and little Andamans. The Great Andamans arc separated by narrow creeks into the North Andaman. Middle Andaman, South Andaman. Baratang and Rutland islands. In addition there are two volcanic islands, e.g Barren and Narcondam situated within 80 km cast of the Andamans. Andaman Islands have been formed by the extension of the Tertiary mountain chain of Arakan Yoma.
The Nocobar Group of Islands comprises 18 islands of which (Car Nicobar, Chowra, Tercssa. Bompoka, Camorta, Trinkat, Nancowry, Katchall, LitlleNicobar(PuloMilo), Great Nicobar and Kondul) arc inhabited and remaining seven (Batti Malav, Tilangchong. Meroe. Trak. Trais, Menchal and Kabra) are uninhabited.
Besides these Arabian Sea and Bay islands India has a number of islands along the Western, Eastern coasts, in the delta region of Ganga and in the Gulf of Mannar.
Among Western Coast islands mention may be made of Piram, Bhaisala (Kathiawar); Diu, Vaida, Nora, Pirtan, Karunbhar( Kachchh coast); Khadiabet, Aliabet (Narmada-Tapi mouth); Butchers, Elephanta, Karanja, Salsette, Cross (near Mumbai); Bhatkal, Pigeoncock, St. Mary (Mangalore coast); Anjidiv (Goa coast); Vypin (near Kochi coast); Pamban, Crocodile, Adunda (Gulf of Mannar); Sri Harikota (mouth of Pulicat lake); Parikud (mouth of Chilka lake); Short, Wheeler (Mahanadi-Brahmani mouth); and New Moore and Sagar (Ganga delta). Many of these are uninhabited and are administered by the adjacent states.