Mount Sinabung

Mount Sinabung (Indonesian: Gunung Sinabung) is a Pleistocene-to-Holocene stratovolcano of andesite and dacite in the Karo plateau of Karo Regency, North Sumatra, Indonesia. Many lava flows are on its flanks and the last known eruption had occurred in the year 1600. Solfataric activity (cracks where steam, gas, and lava are emitted) were last seen at the summit in 1912, but no other documented events had taken place until the eruption in the early hours of 29 August 2010.


Geology
Most of Indonesian volcanism stems from the Sunda Arc, created by the subduction of the Indo-Australian Plate under the Eurasian Plate. This arc is bounded on the north-northwest by the Andaman Islands, a chain of basaltic volcanoes, and on the east by the Banda Arc, also created by subduction.[3]

Sinabung is a long andesitic-dacitic stratovolcano with a total of four volcanic craters, only one being active

On 29 August 2010, the volcano experienced a minor eruption after several days of rumbling.[5] Ash spewed into the atmosphere up to 1.5 kilometres (0.93 mi) and lava was seen overflowing the crater.[5] The volcano had been inactive for centuries with the most recent eruption occurring in 1600.[5]

Mount Sinabung is classified as category “B”, which means it is not necessary for it to be monitored intensively. Other volcanoes, in category “A”, must be monitored frequently, the head of the National Volcanology Agency, named only as Surono, told Xinhua over phone from the province

Wiki