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A series of intense volcanic eruptions at Indonesia’s Mount Anak Krakatau blanketed Jakarta and surrounding provinces in dense ash clouds, forcing suspension of flights at Jakarta airport.
Context
What It Is
TodayNABARD Sprint 60: the 2025 cut-offs and your 60-day Phase I planRegister free →- An active volcanic island and stratovolcano, featuring a pyroclastic cone
- The name means “Child of Krakatoa” in Indonesian
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Formation and Origin
- Emerged within the marine caldera created by the catastrophic 1883 VEI-6 eruption of Krakatoa, which destroyed two-thirds of the original island
- Submarine eruptive activity began in early 1927
- Repeated cycles of basaltic accumulation breached the ocean surface, rising permanently above sea level on 11 August 1930
Important Facts for Examsmost asked
- Anak Krakatau — “Child of Krakatoa”; in the Sunda Strait, between Java and Sumatra, Indonesia
- Emerged from the caldera of the 1883 Krakatoa eruption (VEI-6); rose above sea level on 11 August 1930
- Lies within Ujung Kulon National Park, a UNESCO World Heritage Site and last refuge of the Javan rhinoceros
- On the Pacific Ring of Fire; about 700 km north of the Sunda Trench
- Indo-Australian Plate subducts beneath the Sunda Plate — a convergent boundary
- December 2018 flank collapse caused the Sunda Strait tsunami — a volcanogenic tsunami, not seismic, which is why no earthquake warning preceded it
- VEI — Volcanic Explosivity Index, a 0–8 logarithmic scale
- Eruption types: Strombolian (mild, frequent bursts), Vulcanian (more explosive, ash-rich), Plinian (most violent)
- Stratovolcano — a steep, layered cone of lava and pyroclastic material; Somma volcano — a new cone growing inside an older caldera
- Indonesia has the most active volcanoes of any country; other notable ones: Merapi, Tambora, Semeru, Sinabung
- Mount Tambora (1815) was the largest eruption in recorded history, causing the “Year Without a Summer” in 1816
