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Barren Island volcano in the Andaman basin is active

Barren Island volcano, located 140 km Northeast of Port Blair, is active and spewing smoke and lava again as reported by a team of scientists from CSIR-National Institute of Oceanography (CSIR-NIO), Goa.
The scientific team led by Chief Scientist Dr Abhay V Mudholkar, on board CSIR-NIO’s research ship RV Sindhu Sankalp were busy collecting sea floor samples in the Andaman Basin near the Barren volcano when they witnessed the sudden spewing of ash on January 23,2017.

The team immediately sprang into action and stood as close as one mile from the volcano. Some of the observations noted by them were that the volcano was erupting in small episodes lasting about 5 to 10 minutes.They spent a few hours looking at these episodes and collecting various samples.

photo credit- National Institute of Oceanography, Goa

photo credit- National Institute of Oceanography, Goa

Chief Scientist Dr. B.Nagender Nath and his team revisited the volcano site on January 26 again during the second leg of the cruise and witnessed the continuation of spurts of blasts and smoke.
In a conversation with GnY, Dr Nath said, “We were there to collect and study geological samples when we observed the volcanic eruptions. We were one mile away from the island itself observing smoke coming out. There wasn’t huge lava flow, and the eruptions were occurring in small episodes. We spend 3-4 hours and saw the eruptions on two days”

He added, “During daytime only ash clouds were observed. However after sundown, the team observed red lava fountains spewing from the crater into the atmosphere and hot lava flows streaming down the slopes of the volcano.”

Dr Nath and his team collected samples of sediments and water in the vicinity of the volcano and recovered coal-like black pyroclastic material representing proximal volcanic ejecta. Clouds were seen at the crater mouth where the smoke was bellowing out in otherwise clear sky.

The team observed the activity for about 4 hours before continuing with their research cruise. They did not attempt to land on Barren island volcano as it was too dangerous. The island is about three kilometers in diameter and has a big crater of the volcano, about half a kilometer away from the shore. Private Citizens of India can visit Barren Island volcano by chartered boats after obtaining permission of the Forest Department in Port Blair.

The Andaman Basin is an active back-arc spreading basin and is known for its strong seismicity and many submarine volcanoes and hydrothermal activity. Scientists from CSIR-NIO have been surveying the Andaman Basin and they have identified many small submerged volcanoes in a linear chain called a volcanic arc.

Dr Abhay V Mudholkar said, “These volcanoes are formed due to the rising magma formed deep in the mantle due to the melting of the subducted Indian Ocean crust. A few of these submarine volcanoes have been dredged for samples and pumice type of light volcanic rock have been recovered.”

Endnote

Researchers from CSIR-NIO have been studying the past volcanic events in Andaman Basin based on the ash layers in a sediment column.These samples will help in deciphering the nature of the present and past volcanic activity in the region.Barren Island volcano is uninhabited and the northern part of the island is, as the name suggests,barren and devoid of vegetation.

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