128 Lake Toba in Sumatra.
The Toba eruption (the Toba event) occurred at what is now Lake Toba about 67,500 to
75,500 years ago. It had an estimated Volcanic Explosivity Index of 8 (described as "mega-colossal"), making it possibly the largest explosive volcanic eruption within the last twenty-five million years. The total amount of erupted material was about 2800 cubic km
(670 cubic miles) — around 2,000 km of ignimbrite that flowed over the ground and around 800 km that fellas ash, with the wind blowing most of it to the west. By contrast, the 1980 eruption of Mount St. Helens ejected around 1.2 cubic km of material, whilst the largest volcanic eruption in historic times, at Mount Tambora in 1815, emitted the equivalent of around 100 cubic kilometers of dense rock and created the "Year Without a Summer" as faraway as North America" The Toba eruption was the latest of a series of at least three calderra-forming eruptions which have occurred at the volcano. Earlier calderas were formed around 700,000 and
840,000 years ago. To give an idea of its magnitude, consider that although the eruption took place in Indonesia, it deposited an ash layer approximately 15 cm (6 in) thick over the entire Indian subcontinent atone site in central India, the Toba ash layer today is up tomb bfeet) thick and parts of Malaysia were covered with 9 m of ashfall. In addition it has
been calculated that 1010 metric tons of sulphuric acid was ejected into the atmos-
phere by the event, causing acid rain fallout" -- Reference Wikipedia.org back to 128)
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