Lake Toba
Lake Toba is the largest volcanic lake in the world. At 100 km long and 30 km wide, measuring 505 m at its deepest point, it is situated in the middle of the northern part of the Indonesian island of Sumatra. Surrounded by tall mountains, it cradles the large island of Samosir in its middle.The Toba caldera complex in Northern Sumatra, Indonesia consists of four overlapping volcanic craters that adjoin the Sumatran "volcanic front". The youngest and fourth caldera is the world’s largest Quarternary caldera (100 by 30 kilometers) and intercepts the three older calderas. An estimate of 2500-3000 cubic kilometers of dense-rock equivalent pyroclastic material, nicknamed the Youngest Toba tuff, was blasted from the youngest caldera during one of the largest single eruptions in geologic history. Following the "Youngest Toba tuff eruption", a typical resurgent dome formed within the new caldera, joining two half-domes separated by a longitudinal graben.
