Description

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Context

Indonesia Mount Marapi erupted releasing a 1.5 km high ash plume & triggering a level two alert with a 3 km exclusion zone highlighting region volatile tectonic activity.

Mount Marapi

Attribute	Details
Name	Mount Marapi (also known as Gunung Marapi)
Location	West Sumatra, Indonesia
Geographical Coordinates	Latitude: 0.38° S; Longitude: 100.47° E
Elevation	Approximately 2,891 meters (9,485 feet) above sea level
Volcano Type	Stratovolcano (composite volcano)
Tectonic Setting	Located on Sunda Arc a volcanic arc formed by subduction of Indo Australian Plate beneath Eurasian Plate
Volcanic Arc/Belt	Sunda Arc (part of Pacific Ring of Fire)
Volcanic Status	Active
Latest Eruption	April 2025 (current eruption: 1.5 km ash column, level 2 alert, 3 km exclusion zone)
Previous Major Eruption	December 2023 killed 24 climbers; one of deadliest in recent years
Eruption History	Known for frequent but moderate eruptions Over 50 recorded eruptions since 18th century Typically explosive (Vulcanian style)
Volcanic Explosivity Index (VEI)	Typically ranges between VEI 2 & VEI 3
Current Alert Level	Level II (Waspada) Third-highest alert in Indonesian four-tier system
Exclusion Zone	3 km (9,800 ft) radius from summit
Nearby Cities/Towns	Bukittinggi, Padang Panjang & Batusangkar
Surrounding Population	Thousands live within 10–15 km of volcano
Hazards Associated	Ashfall Pyroclastic flows Lava domes Lahars Volcanic bombs Sudden explosions
Monitoring Agency	Center for Volcanology & Geological Hazard Mitigation (PVMBG), Indonesia
Instruments Used	Seismographs, tiltmeters, gas spectrometers, thermal imaging, drone surveillance
Historical Impact	Periodic evacuations, disrupted agriculture & air traffic; 2023 eruption caused high-profile fatalities among hikers
Cultural Significance	Considered sacred by local Minangkabau communities
Climbing Activity	Popular for hiking & climbing (though often closed due to activity)
Access Route	Main access from Bukittinggi; commonly via Koto Baru or other local villages
Comparison with Mount Merapi	Often confused with Mount Merapi in Central Java both are active & dangerous stratovolcanoes
Preparedness Measures	Sirens & SMS alerts in nearby towns Community evacuation drills Real time monitoring stations
Global Significance	Example of subduction-related stratovolcanoes; important for volcanic research & disaster resilience studies

Major Active Volcanoes in Asia

Volcano Name	Country	Type	Elevation	Last Major Eruption	Volcanic Belt	Notable Features / Hazards
Mount Marapi	Indonesia	Stratovolcano	2,891 m	April 2025	Sunda Arc	Frequent eruptions, fatalities in 2023
Mount Merapi	Indonesia (Java)	Stratovolcano	2,930 m	Jan 2021 (ongoing activity)	Sunda Arc	One of Indonesia most active, close to Yogyakarta
Mount Sinabung	Indonesia (Sumatra)	Stratovolcano	2,460 m	March 2021	Sunda Arc	Reactivated after 400 years in 2010
Mount Semeru	Indonesia (Java)	Stratovolcano	3,676 m	2023	Sunda Arc	Indonesia highest volcano
Mount Mayon	Philippines	Stratovolcano	2,463 m	2023	Luzon Volcanic Arc	Perfect cone shape, very active
Taal Volcano	Philippines	Caldera	311 m	2022	Macolod Corridor	Located in lake, risk of phreatic eruptions
Mount Pinatubo	Philippines	Stratovolcano	1,486 m	1991 (catastrophic)	Luzon Arc	Global impact on climate in 1991 eruption
Sakurajima	Japan	Stratovolcano	1,117 m	Active daily	Ryukyu Arc	Continuous activity, near populated areas
Mount Aso	Japan	Caldera	1,592 m	2021	Nankai Trough Zone	One of world’s largest calderas
Mount Fuji	Japan	Stratovolcano	3,776 m	Last in 1707	Izu–Bonin–Mariana Arc	Dormant but closely monitored
Krakatoa (Anak Krakatau)	Indonesia	Caldera/Island	~813 m (fluctuating)	2018–present	Sunda Strait	1883 eruption among deadliest
Mount Damavand	Iran	Stratovolcano	5,610 m	Holocene (dormant active)	Alborz Range	Highest volcano in Asia
Kunlun Volcanic Group	China	Volcanic field	~5,800 m	~1951	Tibetan Plateau	Least studied, remote region
Paektu (Baekdu) Mountain	North Korea/China	Caldera	2,744 m	946 AD (major), minor activity now	Baekdu Range	Politically sensitive monitoring

Important Technical Terms Related to Volcanoes

Term	Definition
Stratovolcano (Composite)	Tall, conical volcano made of layers of lava, ash & rocks; often explosive (e.g Mt. Fuji, Merapi)
Shield Volcano	Broad, gently sloping sides formed by low viscosity lava (e.g Mauna Loa in Hawaii)
Caldera	A large, basin-like depression formed after collapse of a volcano summit
Pyroclastic Flow	Fast-moving cloud of hot gas, ash & volcanic matter extremely deadly
Lahar	Volcanic mudflow or debris flow often triggered by heavy rains or melting snow
Tephra	Fragmented material ejected during eruptions (includes ash, lapilli, volcanic bombs)
Magma	Molten rock beneath Earth surface
Lava	Molten rock that erupts onto surface
Volcanic Ash	Fine particles of pulverized rock, minerals & glass from volcanic eruptions
Vent	Opening in Earth’s crust through which magma & gases are expelled
Crater	Bowl-shaped depression at top of a volcano
Fumarole	Opening that emits steam & volcanic gases
Phreatic Eruption	Steam driven explosion without magma ejection caused by groundwater heating
Phreatomagmatic Eruption	Explosive eruption involving interaction between water & magma
Volcanic Explosivity Index (VEI)	Scale from 0 to 8 that measures size & explosiveness of eruptions
Hotspot Volcano	Volcano not at plate boundary but caused by mantle plume (e.g Hawaii)
Ring of Fire	Seismically active zone encircling Pacific Ocean with many active volcanoes & earthquakes
Tuff	Rock formed from volcanic ash layers that have compacted & solidified
Volcanology	The scientific study of volcanoes, lava, magma & related phenomena
Seismograph	Instrument to record earthquake waves & volcanic tremors

For more information, please refer to IAS GYAN

Sources: BBC

PRACTICE QUESTION

Q. Discuss strategic importance & disaster management challenges posed by active volcanoes in Asia with special reference to Mount Marapi & Pacific Ring of Fire.