Lake Toba lies near the Great Sumatran fault , which runs along the centre of Sumatra in the Sumatra Fracture Zone . The volcanoes of Sumatra and Java are part of the Sunda Arc , a result of the northeasterly movement of the Indo-Australian Plate , which is sliding under the eastward-moving Eurasian Plate . The subduction zone in this area is very active : the seabed near the west coast of Sumatra has had several major earthquakes since 1995 , including the 9.1 2004 Indian Ocean earthquake and the 8.7 2005 Nias – Simeulue earthquake , the epicenters of which were around from Toba
2004 Indian Ocean earthquake
2004 Indian Ocean earthquake and tsunami
Lake Toba