North Sumatra, Sorikmarapi volcano
Sorik Marapi is a 2145 m high stratovolcano with a crater lake. It is located in Kotanopan of South Tapanuli Regency, North Sumatra, 20 km east of Maura Soma.
There are two crater lakes at the summit. The main crater where the recent activity of the volcano taken place. There are two fumaroles inside this crater. The second one has not been studied.
Phreatic eruptions have occurred at the summit and flank craters over the past two centuries. Hot springs and boiling mud pools are found at summit area. Fumaroles are found on the flanks, such as Sibangor Julu Complex and Sibangor Tonga.
Sorik Marapi volcano was raised to level 2 alert on 3rd August 2011 after continuous volcanic tremor was recorded. Earthquake activity was accompanied by 8 explosions and thick grey emissions rising 1 km above the summit. A 3 km exclusion zone was placed around the crater.
Sorik Marapi Volcano Eruptions
1987. Phreatic eruption. Ashfall around the crater.
1986. Phreatic eruption in main crater. Ashfall to 300m away.
1970. Phreatic eruption at main crater with ashfall.
1917. Phreatic eruption at Merah Lake producing ash.
1893. Phreatic eruption from Sibangor Julu.
1892. Phreatic eruption on the east slope of Siunik. 100 people killed from lahars. 1879. Phreatic eruption in main crater producing mud fountains.
1830. Phreatic eruption in main crater producing ashfall 52 km away.
Subregion Name: Sumatra (Indonesia)
Volcano Number: 0601-12=
Volcano Type: Stratovolcano
Volcano Status: Historical
Last Known Eruption: 1986
Summit Elevation: 2145 m 7,037 feet
Latitude: 0.686°N 0°41’9″N
Longitude: 99.539°E 99°32’22″E
Sorikmarapi is a forested stratovolcano with a 600-m-wide summit crater containing a crater lake and substantial sulfur deposits. A smaller parasitic crater (Danau Merah) on the upper SE flank also contains a crater lake; these two craters and a series of smaller explosion pits occur along a NW-SE line. Several solfatara fields are located on the eastern flank. Phreatic eruptions have occurred from summit and flank vents during the 19th and 20th centuries.