Lake Toba is a popular lake in North Sumatra with its beautiful natural scenery.
The green expanse of the surrounding hills, as well as the blue lake with Samosir Island in the middle is a picture of the beauty of this place.
Lake Toba keeps the power of nature. Behind the vast, beautiful stretch of lake, Lake Toba is a mountain which then erupted violently. Now, a giant volcano (supervolcano) resides under Lake Toba (Toba Caldera). Mount Toba erupted about 74,000 years ago ejecting 2,800 cubic kilometers of magma.
The eruption was scale 8 in the Volcano Explosivity Index (VEI), the strongest in the last two million years. The hot clouds of the Toba eruption reached an area of 20,000 square kilometers.
These hot clouds have piled up almost the entire mainland of Sumatra, from the Indian Ocean in the west to the Malacca Strait in the east with an average thickness of 100 meters of material and in some areas up to 400 meters.
The spread of dust from the eruption of Mount Toba is very wide, almost all over the world, there is evidence of the same form of volcanic dust molecules at 2100 points from the crater caldera which is now Lake Toba in Indonesia, up to 3000 miles, from the source of the eruption.
Even surprisingly enough, it turns out that the spread of the dust has been recorded as far as the North Pole. This reminds experts, how powerful the Toba volcano eruption was at that time.
This tecto-volcanic lake is the largest lake in Southeast Asia because it has a length of 87 kilometers, a width of 27 kilometers, and an altitude of 904 meters above sea level. And the depth reaches 505 meters.
The Super Volcano eruption of Mount Toba originated from the turbulence under the hyperactive earth. The Indo-Australian oceanic plate contains a submerged layer of sediment under the Eurasian continental plate, where Sumatra Island sits, at a rate of 7 centimeters per year.
The friction of the two plates at a depth of about 150 kilometers below the earth creates heat that melts the rock, then rises upward as magma. The more sediment that enters into it, the more sources of magma.
After the eruption, a caldera was formed which then filled with water and became what is now known as Lake Toba. Upward pressure by magma that has not yet been released causes the appearance of Samosir Island.