Raung

Geography & Climate

Raung is located in Indonesia, within the Sunda Volcanic Arc of the broader Sunda-Banda Volcanic Regions. Situated at 8.12° S, 114.06° E in the Southern Hemisphere, the volcano lies within a tropical climate zone. At 3,260 meters above sea level, Raung rises above the surrounding terrain into montane or subalpine conditions. The elevation creates distinct ecological zones along its flanks, from forested lower slopes to exposed rocky terrain near the summit. The volcanic landform is characterized as a composite, which describes the physical shape and structure of the volcanic edifice as observed from the surface.

Geological Context

Raung sits in a subduction zone, where one tectonic plate dives beneath another, creating intense heat and pressure that generates magma. Subduction zones are responsible for many of the world's most explosive volcanoes and deadliest eruptions. For communities in Indonesia near Raung, this tectonic setting means the volcano is capable of producing powerful explosive eruptions, pyroclastic flows, and lahars that can threaten populated areas within tens of kilometers of the summit. The dominant rock type is andesite / basaltic andesite, a dark, fine-grained volcanic rock that forms from rapidly cooling, low-viscosity lava. Basaltic eruptions tend to be less explosive and produce fluid lava flows that can travel long distances. While less immediately dangerous than explosive eruptions, basaltic lava flows can destroy structures and infrastructure in their path, and volcanic gases released during these eruptions can affect air quality over a wide area.

Eruption History Summary

Raung has 76 recorded eruptions in the geological database, spanning from 1586 CE to 2025 CE. The most powerful recorded event was a paroxysmal eruption with devastating regional consequences in 1593 CE, reaching VEI 5 on the Volcanic Explosivity Index. Notable eruptions include 1982 CE (VEI 3), 1956 CE (VEI 3), 1953 CE (VEI 3). With an average interval of roughly 6 years between eruptions over a span of 439 years, this is one of the more frequently active volcanoes in the database. This persistent activity suggests a robust and well-supplied magma system beneath the volcano. With eruptive activity as recently as 2025 CE, Raung remains an actively monitored volcano.

Significance

With a maximum recorded VEI of 5, Raung has demonstrated the capacity for paroxysmal eruptions comparable to the 1980 eruption of Mount St. Helens. Eruptions of this scale can devastate areas within 20-30 kilometers and produce ash fall that disrupts aviation and agriculture across hundreds of kilometers. Its 76 recorded eruptions make it one of the most prolific volcanoes in the entire global volcanic record, reflecting an exceptionally persistent magma supply system that has sustained near-continuous eruptive activity over millennia. Given its recent activity, Raung is closely monitored by geological survey organizations to provide early warning of future unrest.

GVP Reference Summary

Raung, one of Java's most active volcanoes, is a massive stratovolcano in easternmost Java that was constructed SW of the rim of Ijen caldera. The unvegetated summit is truncated by a dramatic steep-walled, 2-km-wide caldera that has been the site of frequent historical eruptions. A prehistoric collapse of Gunung Gadung on the W flank produced a large debris avalanche that traveled 79 km, reaching nearly to the Indian Ocean. Raung contains several centers constructed along a NE-SW line, with Gunung Suket and Gunung Gadung stratovolcanoes being located to the NE and W, respectively.

— Smithsonian Institution, Global Volcanism Program