Volcano Mount Merapi, which erupted in January 2021, is situated in

Q: What is the answer to CAPF 2021 Paper I Q111?

C. Correct — C, Indonesia. Mount Merapi stands on the boundary of Central Java and Yogyakarta, about 2,930 metres high and some 30 kilometres north of the city of Yogyakarta. It is among the most continuously active volcanoes anywhere, and it produced fresh lava avalanches and hot cloud emissions in January 2021, which is what puts it in this paper. Its position is not accidental: Indonesia sits where the Indo-Australian plate is being pushed under the Eurasian plate, a subduction zone along the Pacific Ring of Fire that has given the country more active volcanoes than any other. (Provisional — pending the official UPSC key.)

(a)Thailand
(b)China
(c)Indonesia
(d)Maldives

Answer

Why

Correct — C, Indonesia. Mount Merapi stands on the boundary of Central Java and Yogyakarta, about 2,930 metres high and some 30 kilometres north of the city of Yogyakarta. It is among the most continuously active volcanoes anywhere, and it produced fresh lava avalanches and hot cloud emissions in January 2021, which is what puts it in this paper. Its position is not accidental: Indonesia sits where the Indo-Australian plate is being pushed under the Eurasian plate, a subduction zone along the Pacific Ring of Fire that has given the country more active volcanoes than any other.

Why the others are wrong

(a)Thailand — Thailand lies away from the active plate margin and has no active volcanoes; its geology is dominated by old, worn-down ranges rather than a subduction arc.
(b)China — China does have volcanoes — Changbaishan on the Korean border among them — but Merapi is not one of them, and China is not part of the Indonesian arc.
(d)Maldives — The Maldives are low coral atolls built on the Chagos-Laccadive ridge, with no active volcanism at all. Their highest natural point is a couple of metres above the sea.

Concept

The Ring of Fire is the horseshoe of subduction zones around the Pacific, and about three-quarters of the world's active volcanoes lie along it. Indonesia occupies the segment where the Indo-Australian plate descends beneath the Eurasian, producing the island arc from Sumatra through Java to the Lesser Sundas. Merapi, Krakatoa and Tambora all belong to it, and so do the volcanic soils that make Java one of the most densely settled islands on earth.

Elimination is quicker than recall here. The Maldives are coral atolls, Thailand has no active volcano, and Merapi is not a Chinese name or a Chinese peak. What is worth carrying away is why Indonesia keeps appearing in questions of this kind — it has the largest number of active volcanoes of any country, so a volcano in the news is more often Indonesian than not. Merapi has stayed restless since 2021, with further eruptive episodes in the years after the exam.

Key facts

Merapi lies in Central Java near Yogyakarta and rises to about 2,930 metres.
It is a stratovolcano on the Sunda arc, where the Indo-Australian plate subducts beneath the Eurasian.
Indonesia has more active volcanoes than any other country.
Krakatoa, between Java and Sumatra, and Tambora on Sumbawa are the other Indonesian volcanoes that recur in exams.
Barren Island in the Andaman Sea is India's only confirmed active volcano.

Mount Merapi's forested stratovolcano cone rising to a steaming summit wreathed in cloud, grey ash and lava scars streaking its upper flanks — Mount Merapi in Central Java, a stratovolcano of the Sunda arc and one of the most active volcanoes in the world.Image: Crisco 1492 · Wikimedia Commons (CC BY-SA 3.0)

Study next

The Pacific Ring of Fire and the subduction zones that define itVolcano types — shield, composite, cinder cone, calderaFamous eruptions — Krakatoa 1883 and Tambora 1815Volcanic landforms and volcanic soilsBarren Island and volcanism in Indian territory

Common traps

Confusing Merapi in Java with Marapi in Sumatra, a different volcano with a near-identical name.
Assuming a volcano in the news must be in the Pacific islands rather than the Indonesian arc.

A current-affairs placement item that a candidate can also reach by eliminating three countries on physical geography alone.

Related PYQs

UPSC_2018_GS1_Q852018Open & attempt →

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?

(a) 1 only
(b) 2 and 3
(c) 3 only
(d) 1 and 3

Answer(a) 1 only

The Indian entry on the same arc. Barren Island is the only active volcano in Indian territory, and the reasoning that keeps it active rather than dormant is the same subduction setting that keeps Merapi restless.

CDS_GK_2022_I_Q572022Open & attempt →

Individual lava flows are normally only a few feet thick, but over a long period of time, repeated flows may build up a volcano. Such volcanoes are termed as:

(a) Shield volcano.
(b) Composite volcano.
(c) Strato-volcano.
(d) Cinder-cone volcano.

Answer(a) Shield volcano.

The contrasting build. A shield grows from thin runny flows, while Merapi is a steep composite cone layered from ash and viscous lava — the shape that makes subduction-zone volcanoes explosive.

Practice

practice — not a real PYQ
Mount Merapi is located in which island of Indonesia?
- (a)Sumatra
- (b)Java
- (c)Sulawesi
- (d)Bali
Answer(b) Java — the volcano stands near Yogyakarta in the centre of the island.
practice — not a real PYQ
India's only confirmed active volcano is located at
- (a)Barren Island
- (b)Narcondam
- (c)Majuli
- (d)Baratang
Answer(a) Barren Island — in the Andaman Sea, the only confirmed active volcano in Indian territory.