Rinjani Volcano | John Seach


Lombok, Indonesia

8.42 S, 116.47 E
summit elevation 3726 m

Rinjani is located on the island of Lombok. It is the second highest volcano in Indonesia. Rinjani is located in a caldera 2.4 km by 4.8 km in size.
There are two active centres located in the eastern part of caldera - Barujari and Rombongan cones. Segara Anak Lake is situated inside the caldera.

The western side of the caldera contains a 230 m deep lake, covering an area of 11 sq km and its volume was (before the 2009 eruption) estimated 1.02 cubic km. Rinjani probably contains the largest hot volcanic lake in the world. The lake temperature is 20-22 deg C, which is above the ambient temperature of 14-15 deg C. The lake contains a neutral pH.

2015 Eruption
Rinjani volcano on Lombok, Indonesia erupted on 25th October 2015. The eruption occurred at Barujari cone. Ash emissions reached an altitude of 10,000 ft and extended 40 nautical miles southwest of the volcano. The alert status at Rinjani volcano has been increased to level 2 (waspada). A 3-km radius exclusion was placed around the Rinjani caldera.

2013 Closure to Climbers
Rinjani volcano, was declared closed to climbers for 3 months from 10 Jan 10 to 31 March due to bad weather. Heavy rain had made the track dangerous for trekkers. Closing the volcano to visitors was also designed to let the ecosystem recover.

2009 Eruption
An increase in seismic activity was reported at Rinjani volcano in Indonesia on 2nd May 2009. There were three explosion earthquakes, and a white plume was emitted 1000 m above the eruption point. The alert level at the volcano was raised from Normal (Level I) to Waspada (Level II). The summit was closed to climbers. Residents were warned of possible lahars. On 4th May 2009 ash emissions rose 700 m above the cone. During June 2009 ash emissions reach a height of 3 km above sea level and drifted 55 km from the volcano.

2004 Eruption
Hikers were banned from climbing Mount Rinjani in October 2004 after the volcano after renewed volcanic activity. The volcano is a popular destination for mountain climbers from all over the world. Despite the warning for the hikers, it was not necessary to evacuate villagers living near the volcano. Between 1-5 October eruptions ejected ash columns 800 m above the summit.

1994 Eruption
On 3rd June 1994, Barujari cone erupted and sent ash 500 m high. Between 3rd and 10th June, up to 172 explosions were be heard each day from Sembalun Lawang volcano observatory, located 15 km NE of the volcano. On 3rd November 1994, a cold lahar from the summit area of Rinjani Volcano travelled down the Kokok Jenggak River. Thirty people from the village of Aikmel who were collecting water from the river were killed.

1944 Eruption
A lave dome formed in the crater lake at Rinjani volcano in the second half of 1944. Two islets appeared above the lake surface in its northeastern part, where formerly a depth of 160 meters had been measured.

Great 1257 Eruption of Samalas volcano
Ice core samples of sulphate and tephra recorded an eruption of Samalas volcano between May and October 1257 AD. The eruption produced the largest release of sulphur to the stratosphere in the past 7000 years. This was one of the largest holocene eruptions with 40 cubic km of dense rock equivalent erupted.

Further reading
Rachmat, Heryadi, et al. "Petrogenesis of Rinjani Post-1257-Caldera-Forming-Eruption Lava Flows." Indonesian Journal on Geoscience 3.2 (2016): 107-126.

Lavigne, Franck, et al. "Source of the great AD 1257 mystery eruption unveiled, Samalas volcano, Rinjani Volcanic Complex, Indonesia." Proceedings of the National Academy of Sciences 110.42 (2013): 16742-16747.

Rinjani Volcano Eruptions

2015, 2009, 2004, 1994, 1966, 1965, 1953, 1949-50, 1944-45, 1941?, 1915, 1909, 1906, 1901, 1900, 1884, 1847.