Why is lake toba a lake?

Answer 1

Lake Toba (Indonesian: Danau Toba) is a lake and supervolcano, 10 kilometres long and 30 kilometres wide, and 505 metres (1,666 ft) at its deepest point.Un der it there is a volcano. Located in the middle of the northern part of the Indonesian island of Sumatra with a surface elevation of about 900 metres (2,953 ft), the lake stretches from 2°53′N 98°31′E / 2.88°N 98.52°E / 2.88; 98.52 to 2°21′N 99°06′E / 2.35°N 99.1°E / 2.35; 99.1. It is the largest volcanic lake in the world.[1] In addition, it is the site of a supervolcanic eruption that occurred 74,000 years ago, a massive climate-changing event. The eruption is believed to have a VEI intensity of 8. This eruption, believed to have been the largest anywhere on Earth in the last 25 million years, may have had catastrophic consequences globally; some anthropologists and archeologists believe that it killed most humans then alive, creating a population bottleneck in Central Eastern Africa and India that affected the genetic inheritance of all humans today