Mount Batur is an active volcano located in Kintamani, Bangli District, Bali. The mountain soars to 1,171 meters above sea level. Mount Batur is a part of the Pacific Ring of Fire and becomes one of the most active volcanoes in Indonesia. Noted since 1804, Mount Batur has erupted as much as 26 times. Two large eruptions of tens of thousands of years ago formed a giant crater. The crater now known as Lake Batur, a crescent-shaped lake, fascinates many visitors. Lake Batur has an area of 16 km2. To see it from cultural side, Hindu religion is dominating the Geopark. As seen through breath-taking temples such as Pancering Jagad Temple, Pura Dalem Belingkang, Pura Batur and Pura Bukit Mentik. This area also has a traditional village, Trunyan, which still maintains its tradition.
Mount Sewu has an area up to 1,802 km2, stretching in three areas of Gunungkidul, Wonogiri, and Pacitan. Mount Sewu known as an area formed by the dissolution of limestone (karst). The character of Geopark Sewu comes from its limestone rock hills, caves, underground rivers, waterfalls and contour basins Mount Sewu Geopark considered as a complete tourist destination. Its coastal nature tourism covers the area of Gunung Kidul and various caves in Pacitan. Not to miss, meeting the local community through its creative industry tourism.
Mass migration as the only survival option
The events of the eruption of the 'Super Volcano' of the Toba Caldera turned out to cause various impacts. Among them is the loss of the central partof the island of Sumatra, this happened due to a hot cloud from the 'Super Volcano' eruption. The 'Supervolcano' also caused the pumice and volcanic ashthat stretches from the western to the southwestern regions of Sumatra, the Malay Peninsula, to Indochina and India (Madhya Pradesh).
At its peak, this eruption produced harmful gases and water, which vaporized into the atmosphere even touching the stratosphere layer.This event then triggered what is known as 'volcanic winter', the restriction of sunlight to the earth, causing a prolonged winter. The 'Supervolcano' led to an environmental catastrophe, leading to the death of living things due to loss of food sources to the point of extinction.
The only way to survive at that time was to migrate. Many written records state that the migration not only happened in the region of Sumatra but,due to the massive eruption, the area affected by the 'volcanic winter' was very wide and reached most of Asia. To survive, humans affected bythis volcanic winter migrated to temperature-stable places and the migration helped them to maintain adequate sunlight and food supply.
The emerging island on the island
The presence of the island of Samosir in the vastness of the Toba Caldera is a rare occurrence in the world. This island emerges from below the water surface.
It was the result of the pressure in the magma chamber causing the removal of the base of the caldera. The process is also known as resurgence.
Based on the topsoil data, the island of Samosir was still below the surface of the lake water 30,000 years ago. Since that time, the island of Samosir has undergone lifting as much as ± 700 m with the position tilting to the west. The elevation changes are in close relation to the magmachamber refilling process. The Tuktuk area is the earliest part to have surfaced out of Lake Toba, which happened ± 8,000 years ago.This knowledge is the result of reconstructing the elevation process of the island of Samosir.