On 13 January a volcanic ash advisory statement was issued based on an unspecified naval aircraft report of observed "volcanic emission of smoke" from Barren Island at 1303 GMT. There was no evidence of a plume or ash cloud on either visual or infrared GMS satellite imagery at 0332 or 0425 GMT earlier that day.

Barren Island, a possession of India in the Andaman Sea about 135 km NE of Port Blair in the Andaman Islands, is the only historically active volcano along the N-S-trending volcanic arc extending between Sumatra and Myanmar (Burma). The small, 3-km-wide island contains a 1.6-km-wide somma open to the west with a fresh pyroclastic cone in its center that has been the source of historical eruptions. Lava flows have reached the sea along the western coast during eruptions in the early 19th century and more recently in 1991 and 1995.

Geological Summary. Barren Island, a possession of India in the Andaman Sea about 135 km NE of Port Blair in the Andaman Islands, is the only historically active volcano along the N-S volcanic arc extending between Sumatra and Burma (Myanmar). It is the emergent summit of a volcano that rises from a depth of about 2250 m. The small, uninhabited 3-km-wide island contains a roughly 2-km-wide caldera with walls 250-350 m high. The caldera, which is open to the sea on the west, was created during a major explosive eruption in the late Pleistocene that produced pyroclastic-flow and -surge deposits. Historical eruptions have changed the morphology of the pyroclastic cone in the center of the caldera, and lava flows that fill much of the caldera floor have reached the sea along the western coast.

Information Contacts: Darwin Volcanic Ash Advisory Centre, Bureau of Meteorology, Northern Territory Regional Office, PO Box 40050, Casuarina, Northern Territory 0811, Australia (URL: http://www.bom.gov.au/info/vaac/).