RAS question
The Andaman Islands are the peaks of a submerged mountain range that is an extension of:
Correct answer: (D) Arakan Yoma range of Myanmar.
The Andaman Islands are exposed peaks of a submerged mountain chain that continues southward from Myanmar's Arakan Yoma range.
Explanation
The Andaman Islands are not an isolated mainland extension of peninsular India. The FAO account of Indian coral reefs describes the Andaman and Nicobar group as the emerged part of a mountain chain lying on a ridge that extends southward from the Irrawaddy delta area of Burma and continues the trend of the Arakan Yoma range. This matches the standard explanation that the islands are exposed peaks of a submerged range extending south from Arakan Yoma. The same tectonic setting, parallel to the Indo-Burmese plate boundary, also explains why the region is associated with seismicity and volcanic activity, including Barren Island.
Why the other options are wrong
- (A) The Eastern Ghats are a mainland eastern-India range and do not extend into the Bay of Bengal to form the Andaman island chain.
- (B) The Western Ghats belong to peninsular India's western margin, so they have no geographical link with the Andaman ridge in the Bay of Bengal.
- (C) The Himalayan extension is traced through north-eastern India as the Purvanchal system, not southward into the Andaman chain.
Concept
This tests the physiographic origin of India's island groups, especially the distinction between peninsular ranges and the Indo-Myanmar island arc. It recurs in RAS because island geography links relief, plate setting, earthquakes and volcanism in one map-based concept.