The Ijen volcano complex, situated on the border of Banyuwangi and Bondowoso Regencies in East Java, Indonesia, represents a composite volcanic system of significant scientific interest. Within the complex, the Kawah Ijen crater hosts a hyperacidic lake (pH < 0.3), renowned as the largest such body of water globally. This extreme acidity is attributed to the dissolution of magmatic gases rich in sulfur dioxide and hydrogen chloride. The volcano is further characterized by phreatic eruptions and the emission of sulfuric gases, which combust upon contact with the atmosphere, producing the visually stunning blue flame phenomenon.

Location: East Java, Indonesia
Coordinates: -8.057804, 114.242113
Volcano Type: Stratovolcano


Ijen’s Location


Ijen’s Latest Status

2024: Currently in a state of unrest


Ijen’s Eruptive History

Year Overview
1796 Significant eruption reported, details of the exact nature are limited.
1817 Large eruption lasting several weeks. The crater lake was ejected, and mudflows (lahars) devastated surrounding areas.
1917 Phreatic activity accompanied by a significant increase in the crater lake’s temperature.
1936 Eruption similar in scale to 1817, including crater lake overflow and potential mudflows.
1952 Eruption following a series of strong local earthquakes. Ash ejected up to 1000 meters into the atmosphere.
1993 Series of phreatic eruptions preceded by a change in the lake’s color from whitish-green to brown. Rockfalls observed on the crater walls.
1994 Small phreatic eruption concentrated at the southern end of the crater lake.
1997 Increased seismic activity, changes in lake color, strong sulfuric odor, and reports of gas emissions causing birds to fall into the lake.
1999 Phreatic eruptions accompanied by detonations heard 2 km from the summit and tremor with an amplitude of 0.5 to 1 mm.
2013 Ijen’s crater is now closed due to heightened seismicity.
2020 A powerful gas explosion at Ijen volcano on May 29th sent a plume of ash and gas soaring 250-500 meters above the lake, as reported by PVMBG
2023 Weak emissions and plume rising to 3000 meters.


Ijen Monitoring

For monitoring of Indonesian Volcanoes, please refer to PVMBG.


Ijen Images