"Anak Krakatau Eruption Shuts Eight Indonesian Airports, Raises Tsunami Warning Concerns"
Composite Stratovolcano
a steep, explosive volcano built from alternating layers of lava and pyroclastic material
Flank Collapse
sudden failure of a volcano's outer slope into the sea, generating a tsunami without strong seismic warning
The Sunda Strait, separating the Indonesian islands of Java and Sumatra, sits within the Circum-Pacific Belt, commonly called the Ring of Fire. This belt accounts for roughly 75% of the world's active volcanoes and is the most seismically and volcanically active zone on Earth. The intense activity results from the subduction of the Indo-Australian Plate beneath the Eurasian Plate, generating magma that drives explosive eruptions. Indonesia alone hosts over 130 active volcanoes, making it one of the most volcanically exposed nations on the planet.
The original Krakatau erupted catastrophically in 1883, generating massive tsunamis that killed approximately 36,000 people. Anak Krakatau (meaning 'Child of Krakatau') emerged from the sea in 1927, growing within the caldera left by that earlier event. It is classified as a composite stratovolcano: characterised by viscous lava, explosive eruptions, and alternating layers of lava and pyroclastic material. Composite volcanoes are steeper and more explosive than shield volcanoes, which are built from fluid basaltic lava and produce far less ash dispersal.
India's own active volcano, Barren Island, lies in the Andaman Sea approximately 140 km east of Port Blair (not Great Nicobar, a common misconception). It is India's only confirmed active volcano and sits within the same Indo-Australian subduction zone that drives activity across the broader region. Barren Island has erupted multiple times since 1991, most recently in the 2010s, and remains volcanically active. This shared geophysical setting means that major eruptions in the Sunda Strait region carry indirect relevance for India's own disaster preparedness posture.
A critical hazard that Anak Krakatau poses is flank collapse:
Volcanic ash dispersal is a separate but equally significant hazard. …
Consider the following statements :
1.The Barren Island volcano is an active volcano located in the Indian territory.
2.Barren Island lies about 140 km east of Great Nicobar.
3.The last time the Barren Island volcano erupted was in 1991 and it has remained inactive since then.
Which of the statements given above is/are correct?
Discuss the vulnerability of India to earthquake-related hazards, with examples and salient features of major disasters caused by earthquakes in different parts of India during the last three decades.
Mention the global occurrence of volcanic eruptions in 2021 and their impact on regional environment.
Consider the following statements about Barren Island volcano:
1.It is the only active volcano in Indian territory.
2.It is located approximately 140 km east of Great Nicobar Island.
3.It has erupted multiple times since 1991.
Which of the statements given above is/are correct?
Consider the following statements about Anak Krakatau:
1.It is located in the Sunda Strait between Java and Sumatra.
2.It is classified as a shield volcano characterised by fluid basaltic lava.
3.The 2018 tsunami associated with it was caused by a volcanic flank collapse, not an earthquake.
Which of the statements given above is/are correct?
Consider the following statements about volcanic flank-collapse tsunamis:
1.They produce a strong seismic signal that activates standard tsunami early-warning systems.
2.The Indian Tsunami Early Warning Centre in Hyderabad was designed primarily to detect earthquake-generated tsunamis.
3.The Sendai Framework for Disaster Risk Reduction calls for multi-hazard early-warning systems that cover volcanic tsunami triggers.
Which of the statements given above is/are correct?
Match the following volcanic/tsunami-related institutions with their correct descriptions:
1.Indian Tsunami Early Warning Centre — (a) Located in Hyderabad; monitors seismic signals for tsunami alerts
2.Volcanic Ash Advisory Centres (VAACs) — (b) Operated under WMO; issue ash-cloud advisories to aviation
3.Sendai Framework — (c) 2015–2030 international agreement calling for multi-hazard early-warning systems
Which of the following matchings is correct?
Which of the following correctly describes the geophysical setting of the Sunda Strait region?
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