East Java, Indonesia
8.05 S, 114.24 E,
summit elevation 2386 m
Kawah Ijen is the world's largest acidic volcanic lake. It is located in east Java, Indonesia.
The Ijen volcanic complex consists of several stratovolcanoes and cinder cones and a 20 km wide caldera. Ijen caldera is the largest in Java. The size of the crater is about 960 m x 600 m. The primary dangers at Ijen are pyroclastic flows, lahars, and lava flows.
Ijen volcano 2012
Kawah Ijen 2012
Miners dig sulphur from the active vents at Ijen. Liquid red sulphur erupts from the vents and cools to a yellow colour
Kawah Ijen 2012
Ijen sulphur miner
Ijen sulphur miner, 2012
Kawah Ijen. (pH less than 2)
Thermal springs are located on Ijen lakeshore. The lakeshore fumarole discharges (170-245°C) have both a magmatic and a hydrothermal component.
Post Caldera Eruptions
Post-caldera activity consist of phreatomagmatic, phreatic, strombolian and plinian eruptions from 22 separate vents. Current volcanic activity is located at Kawah Ijen which has a depth of 200-300 m. Most eruptions at the volcano have been phreatic.
Between 8-13 December 2011 harmonic tremor and 77 shallow volcanic earthquakes were recorded at the volcano. Seismicity began to increase in October 2011 and continued high levels of shallow volcanic earthquakes have continued at the volcano into December. Between 1-13 December visual observations showed brown-white emissions with a weak pressure rising 50-200 m above the crater. On 15th December 2011 the alert status at Ijen volcano was raised to level 2 (out of a maximum 4). A 1 km exclusion zone was placed around the crater. This affected both visitors and sulphur miners.
An increase in activity at Kawah Ijen resulted in the area being closed to visitors in June 2004. The lake changed colour from green to white, sulphurous rocks and foam were emitted.
A small explosion occurred at Ijen volcano on 29th July 2002. Ash emissions continued until mid August.
Sulphur emissions entered the cabin of a Singapore to Denpasar flight on 15th July 2000. Ijen volcano was suspected as the source of the emissions. Gray was emissions occurred from the volcano in mid August.
Two phreatic explosions occurred on 28th June 1999. The eruptions were heard 2 km from the lake.
On 3rd February 1994, a small phreatic eruption occurred at the southern end of the crater lake.
Three phreatic eruptions occurred at Ijen volcano on 3-4 July 1993. Eruption were preceded by a change in lake colour from whitish-green to brown. On 5th July rockfalls were observed at the inner crater south wall. Another phreatic eruption occurred on 7th July, with rumbling noises heard at the sulphur weighing station 750 m from the lake. Two phreatic eruptions occurred on 1st August and were heard at the weighing station.
Upwelling eruptions began at Kawah Ijen on 7th November 1936. Between 7-14 November the eruptions occurred west of the deepest part of the lake at a depth of 170 m. On 15th November, eruptions occurred 200 m ESE at a depth of 198 m. During the larger eruptions, waves swept over the weir on the western side of the lake. Eruptions stopped on 17th November.
The eruption of Ijen in 1817 lasted 33 days. The crater lake was ejected. Large areas around the volcano were inundated, especially the plain of Rogodiambi. Several villages were destroyed, and many people and animals killed.
2002, 2000, 1999, 1994, 1993, 1952, 1936, 1917, 1817, 1796.
640 BC ± 50 yr (most recent magmatic eruption).