Based on a pilot observation, the Darwin VAAC reported a lava flow from Barren Island on 17 November. A possible low-level ash plume was seen drifting W on satellite imagery. On 18 November, a pilot reported that an ash plume rose to an altitude of 2.4 km (8,000 ft) a.s.l. and drifted WSW.

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.

Source: Darwin Volcanic Ash Advisory Centre (VAAC)