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What kinds of rocks form the Andaman and Nicobar Islands?
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Andaman and Nicobar Islands
Andaman redwood trees in the Cinque Islands, south of Rutland Island, in the southern Andamans, Andaman and Nicobar Islands, India.
The Andaman and Nicobar Islands are primarily composed of sandstone, limestone, and shale. These rock formations are of Cenozoic age, dating back approximately 2.6 to 65 million years (specifically spanning the Neogene and Paleogene periods).12
Geologically, these islands represent the above-sea extensions of submarine ridges that form a great island arc, connecting the Rakhine Mountains and the Patkai Range in the north to the Mentawai Ridge in the south. In addition to these sedimentary rock types, some areas of the archipelago, such as Car Nicobar, feature surfaces covered by coral formations.1