Mount Batur ''(Gunung Batur)'' is an active volcano located at the center of two concentric

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...

s north west of Mount Agung on the island of

Bali Bali () is a province of Indonesia and the westernmost of the Lesser Sunda Islands. East of Java and west of Lombok, the province includes the island of Bali and a few smaller neighbouring islands, notably Nusa Penida, Nusa Lembongan, and ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Gui ...

. The south east side of the larger 10×13 km caldera contains a caldera lake. Both the larger caldera, and a smaller 7.5 km caldera were formed by a collapse of the magma chamber, the first larger collapse taking place about 29,300 years ago, and the second inner caldera collapsing about 20,150 years ago. Another estimate of the inner caldera's formation date, formed during emplacement of the Bali (or

Ubud Ubud is a town on the Indonesian island of Bali in Ubud District, located amongst rice paddies and steep ravines in the central foothills of the Gianyar regency. Promoted as an arts and culture centre, it has developed a large tourism industry ...

)

ignimbrite Ignimbrite is a type of volcanic rock, consisting of hardened tuff. Ignimbrites form from the deposits of pyroclastic flows, which are a hot suspension of particles and gases flowing rapidly from a volcano, driven by being denser than the surro ...

, has been dated at about 23,670 and 28,500 years ago. The first documented eruption was in 1804 and the most recent was in 2000.

Active volcano and Lake Batur in the caldera

The eruption that brought this volcano to be visible above the ocean is one of the most forceful across the Earth. This volcano is marked by a collapsed top, called a

. The southeast wall of the inner caldera lies beneath

Lake Batur Lake Batur is a volcanic crater lake in Kintamani, Bali, Bangli Regency of Bali, located about northeast of Ubud in Bali. The lake is inside of the caldera of an active volcano, Mount Batur, located along the Ring of Fire of volcanic activity. ...

; Batur cone has been constructed within the inner caldera to a height above the outer caldera rim. The Batur

stratovolcano A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with a summit crater and peri ...

has produced vents over much of the inner caldera, but a NE-SW fissure system has localized the Batur I, II, and III craters along the summit ridge. Historical eruptions have been characterized by mild-to-moderate explosive activity sometimes accompanied by

lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or ...

emission.

Basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90 ...

ic lava flows from both summit and flank vents have reached the caldera floor and the shores of Lake Batur over its history. The caldera contains an active, 700-metre-tall

rising above the surface of Lake Batur. The first documented eruption of Batur was in 1804, and it has been frequently active since then, most recently in 2000. The substantial lava field from the 1968 eruption is visible today when viewed from Kintamani, a town on the southwest ridge of the caldera.

Villages in the caldera

The caldera is populated and includes the four main villages of Kedisan, Songan,

Trunyan Trunyan or Terunyan is a Balinese village (''banjar'') located on the eastern shore of Lake Batur, a caldera lake in Bangli Regency, central Bali, Indonesia. The village is one of the most notable homes of the Bali Aga people, the others being ...

and Toya Bungkah, among a total of 15 villages. The locals largely rely on agriculture for income but tourism has become increasingly popular due to the relatively straightforward trek to the summit of the central crater.

Global Geoparks Network

On 20 September 2012

UNESCO The United Nations Educational, Scientific and Cultural Organization is a List of specialized agencies of the United Nations, specialized agency of the United Nations (UN) aimed at promoting world peace and security through international coope ...

made Mount Batur Caldera a part of the

Global Geoparks Network UNESCO Global Geoparks (UGGp) are geoparks certified by the UNESCO Global Geoparks Council as meeting all the requirements for belonging to the Global Geoparks Network (GGN). The GGN is both a network of geoparks and the agency of the United Nati ...

Sedimentation

Heavy sedimentation in Mount Batur Caldera decreases the water in the lake. A plan was devised to restrict locations around the lake for tourist accommodations, to inform residents of the problems of fish farm cages in the lake, and perhaps to dredge some of the natural sedimentation from volcanic ash. The lake is subject to water pollution from fishing and agricultural run off, promoting the growth of too many

water hyacinths ''Pontederia crassipes'' (formerly ''Eichhornia crassipes''), commonly known as common water hyacinth is an aquatic plant native to South America, naturalized throughout the world, and often invasive outside its native range.List of volcanoes in Indonesia The geography of Indonesia is dominated by volcanoes that are formed due to subduction zones between the Eurasian plate and the Indo-Australian plate. Some of the volcanoes are notable for their eruptions, for instance, Krakatoa for its globa ...

References

External links

* * {{DEFAULTSORT:Batur Geoparks in Indonesia Calderas of Indonesia Subduction volcanoes Volcanoes of Bali Volcanic crater lakes Active volcanoes of Indonesia Bangli Regency VEI-7 volcanoes