Sirung

Geography & Climate

Sirung is located in Indonesia, within the Sunda Volcanic Arc of the broader Sunda-Banda Volcanic Regions. Situated at 8.50° S, 124.13° E in the Southern Hemisphere, the volcano lies within a tropical climate zone. With a summit elevation of 1,347 meters above sea level, Sirung is a moderately sized peak that remains accessible to hikers and researchers for much of the year. 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

Sirung 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 Sirung, 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

Sirung has 14 recorded eruptions in the geological database, spanning from 1852 CE to 2021 CE. The most powerful recorded event was an explosive event producing ash plumes up to several kilometers in 2012 CE, reaching VEI 2 on the Volcanic Explosivity Index. This level of eruptive frequency indicates a persistently active volcanic system that warrants ongoing monitoring. With eruptive activity as recently as 2021 CE, Sirung remains an actively monitored volcano.

Significance

With 14 recorded eruptions, Sirung has a substantial eruptive history that provides valuable data for understanding volcanic behavior and assessing future hazards in the Sunda-Banda Volcanic Regions region. Given its recent activity, Sirung is closely monitored by geological survey organizations to provide early warning of future unrest.

GVP Reference Summary

Sirung is located at the NE end of a volcanic massif with multiple centers that extends 14 km NE from the southern end of Pantar Island. The volcano is truncated by a 2-km-wide caldera whose floor often contains one or more small lakes. Much of the volcano is constructed of basaltic lava flows, and the Gunung Sirung lava dome forms the high point on the caldera's western rim. A number of phreatic eruptions occurred from vents within the caldera during the 20th century. Forested Gunung Topaki, the high point of the volcanic chain, has a small summit crater and lies ~3.5 km SW of the active crater area.

— Smithsonian Institution, Global Volcanism Program