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.
Banua Wuhu submarine volcano rises more than 400 m from the sea floor in the Sangihe Islands. Historical records show that several ephemeral islands were formed and disappeared. A 90 m high of island was formed in 1835, but then dwindled to only a few rocks in 1848. A new island was reportedly formed in 1889 and it was 50 m high in 1894. Another new island was formed in 1919 but then disappeared by 1935.