Barren Island

India’s Only Active Volcano

• Where it sits: Barren Island lies in the Andaman Sea, part of the Andaman and Nicobar Islands.
• A rare title: it is India’s only confirmed active volcano. It is also the only confirmed one in all of South Asia.
• Distance: the island sits about 138 km northeast of Port Blair. Port Blair is the capital of the Andaman and Nicobar Islands.
• No residents: Barren Island is uninhabited. It covers roughly 3 sq km of land.
• Real height: it rises about 354 metres above the sea. But it climbs almost 2 km more, measured from the seafloor below.
• A long record: its first recorded eruption was in 1787.

Worked example: picture a boat trip near Barren Island, since landing needs special permission. From the water, you would see a bare, cone-shaped island. Smoke or fresh lava could still be rising from its centre.

The Caldera and the Volcanic Arc

• The caldera: Barren Island holds a caldera about 1.6 km wide. It opens toward the west.
• How it formed: a major explosive eruption carved it out. This happened in the late Pleistocene, a very old geological period.
• Part of a chain: Barren Island sits on a volcanic arc. This arc runs north to south, stretching between Sumatra and Myanmar.
• A famous relative: the same arc produced Indonesia’s Krakatoa, one of history’s most famous volcanoes.

Worked example: think of the caldera as an old wound that never fully healed. Every new eruption adds fresh lava inside that same bowl-shaped scar.

The Plate Boundary Behind It

• One shared cause: Barren Island’s volcanism comes from one plate boundary. That same boundary shapes the whole Andaman and Nicobar chain.
• A longer chain: these islands are just the visible top of a much longer underwater mountain range. That range runs the length of the Bay of Bengal.
• Subduction at work: here, the Indian Plate slides underneath the Burmese microplate. This process is called subduction.
• What it produces: subduction melts deep rock into basaltic magma. That magma feeds Barren Island’s eruptions.
• A second effect: this same subduction zone also causes the region’s earthquakes. These quakes are often frequent, and sometimes severe.

Protected Since 1987

• The declaration: India’s government made Barren Island a Wildlife Sanctuary. This happened on 16 February 1987.
• What it protects: the sanctuary covers the coral reefs and marine life around the island.
• Restricted access: landing on Barren Island needs special permission from the Andaman and Nicobar administration.
• Why the restriction: two reasons explain this rule. Real volcanic risk is one. How fragile the island’s nature is, is the other.
• Mostly viewed, rarely visited: most tourists only see Barren Island from a boat offshore. Actual landings stay rare, and are mainly for scientific research.
• Slowly growing: repeated lava flows reshape the coastline over time. Each fresh flow adds a small patch of new land. In a real sense, the island is still growing.

Narcondam’s Dormant Cone

• Where it sits: Narcondam Island lies about 140 km north-northeast of Barren Island.
• What it is: Narcondam is a dormant volcanic cone. It also lies within Indian territory.
• What “dormant” means here: Narcondam has not erupted in modern recorded history.
• Not the same as dead: dormant is not the same as extinct. Scientists do not rule out future activity.

Bare Rock and a Few Tough Goats

• A stark landscape: Barren Island is mostly bare volcanic rock. Only hardy grasses and shrubs grow on its outer slopes.
• Where the name comes from: early European sailors likely named it “Barren” for this stark look. Its neighbours look much greener.
• Who lives there: a small population of feral goats lives on the island. Seabirds visit too, despite the harsh terrain.
• Surviving an eruption: the 1991 eruption badly damaged the island’s plants and wildlife. Even so, the goat population managed to recover.
• Where the goats came from: they likely descend from animals released long ago. Sailors kept goats there as a food source, in case of shipwreck.
• Why they survived: goats are famously hardy grazers. That toughness likely explains how such a small herd survived here so long.

Worked example: picture a shipwrecked sailor in the 1800s. He is stranded on this volcanic island, with almost nothing to eat. Goats left behind by an earlier ship could mean the difference between starving and surviving.

Eruption History Since 1787

• A shared fault system: Barren Island sits near one big fault system. That same fault caused the 2004 Indian Ocean earthquake and tsunami.
• A violent restart: a few months after that disaster, the volcano erupted violently again. This active phase ran from 2005 to 2007.
• A long sleep, broken: before that, the volcano stayed quiet for 159 years after early activity. It then woke up in 1991, erupting for six months.
• A dense record: between 1994 and 2022, Barren Island erupted many times. Recorded years include 1994-95, 2005-07, 2008-10, 2013-14, 2017, and 2022.
• Mostly mild: most of these eruptions are Strombolian in style. They bring lava flows and small bursts, not huge explosive blasts.

Watching From a Distance

• Who watches: Indian science agencies watch Barren Island closely. This includes the National Institute of Ocean Technology.
• Global help too: international satellite services also track the volcano.
• Why from a distance: landing safely on the island is hard. So satellite thermal imaging has become the main, most practical way to track it.
• The bigger picture: remote monitoring fits Barren Island’s whole story — genuinely active, but almost never visited.

Still Rumbling in 2026

• The update: Barren Island remains active as of a June 2026 report. It is still the only confirmed active volcano in India and South Asia. (Source: Clarity UPSC)
• Satellite confirmation: satellite reports recorded ash plumes and heat signals from the volcano in early 2026.
• Two more eruptions: two small eruptions happened in September 2025. They made small ash plumes, called “minor” by officials.
• Why it matters: this confirms the volcano is active right now, not only in the history books.