The geography of Indonesia is dominated by volcanoes that are formed due to subduction zones between the Eurasian plate and the Indo-Australian plate. Some of the volcanoes are notable for their eruptions, for instance, Krakatau for its global effects in 1883, Lake Toba for its supervolcanic eruption estimated to have occurred 74,000 Before Present which was responsible for six years of volcanic winter, and Mount Tambora for the most violent eruption in recorded history in 1815.
Sorikmarapi is highly vegetated stratovolcano on Sumatra island, Indonesia. It has 600 m wide of crater lake at the summit and some sulfur deposits. Small parasitic crater, called Danau Merah, is found at the upper southeast flank of the mountain and several solfatara fields at the eastern flank. During the 19th and 20th century, small phreatic eruptions occurred.
