Toba

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  • Indonesia
  • Indonesia
  • Caldera
  • Unknown - Undated Evidence
  • Country
  • Volcanic Region
  • Primary Volcano Type
  • Last Known Eruption
  • 2.58°N
  • 98.83°E

  • 2157 m
    7075 ft

  • 261090
  • Latitude
  • Longitude

  • Summit
    Elevation

  • Volcano
    Number

The Global Volcanism Program has no activity reports for Toba.

The Global Volcanism Program has no Weekly Reports available for Toba.

The Global Volcanism Program has no Bulletin Reports available for Toba.

The 35 x 100 km Toba caldera, the Earth's largest Quaternary caldera, was formed during four major Pleistocene ignimbrite-producing eruptions beginning at 1.2 million years ago. The latest of these produced the Young Toba Tuff (YTT) about 74,000 years ago. The YTT represents the world's largest known Quaternary eruption, ejecting about 2500-3000 cu km (dense rock equivalent) of ignimbrite and airfall ash from vents at the NW and SE ends of present-day Lake Toba. Resurgent doming forming the massive Samosir Island and Uluan Peninsula structural blocks postdated eruption of the YTT. Additional post-YTT eruptions include emplacement of a series of lava domes, growth of the solfatarically active Pusukbukit volcano on the south margin of the caldera, and formation of Tandukbenua volcano at the NW-most rim of the caldera. Lack of vegetation suggests that this volcano may be only a few hundred years old (Chesner and Rose, 1991).

The Global Volcanism Program is not aware of any Holocene eruptions from Toba. If this volcano has had large eruptions (VEI >= 4) prior to 10,000 years ago, information might be found on the Toba page in the LaMEVE (Large Magnitude Explosive Volcanic Eruptions) database, a part of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).

This compilation of synonyms and subsidiary features may not be comprehensive. Features are organized into four major categories: Cones, Craters, Domes, and Thermal Features. Synonyms of features appear indented below the primary name. In some cases additional feature type, elevation, or location details are provided.


Cones

Feature Name Feature Type Elevation Latitude Longitude
Batuharang, Dolok Cone 1552 m 2° 13' 0" N 98° 53' 0" E
Pusukbukit
    Poesoek Boekit
    Nabelberg
Stratovolcano 1972 m 2° 36' 0" N 98° 39' 0" E
Sibutan, Dolok Stratovolcano 2° 59' 0" N 98° 30' 0" E
Singgalang, Dolok Cone 1865 m 2° 57' 0" N 98° 37' 0" E
Tandukbenua, Dolok
    Sipisopiso
Cone 1947 m 2° 56' 0" N 98° 32' 0" E

Craters

Feature Name Feature Type Elevation Latitude Longitude
Haranggaol Caldera
Porsea Caldera
Sibandung Caldera
Lake Toba, the largest lake in SE Asia, fills more than half of the 35 x 100 km Toba caldera, the Earth's largest Quaternary caldera. Caldera walls rise steeply 400-1200 m above the 1700 sq km lake, which is one of the world's deepest, with a maximum depth of 530 m. This view looks south from the northern caldera rim.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey).
The northern wall of Toba caldera rises about 500 m above the village of Haranggoal. Samosir Island, visible in the distance across Lake Toba on the right, is part of an uplifted block of caldera-fill deposits from the last major eruption of Toba about 74,000 years ago.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey)
The 35 x 100 km Toba caldera was formed during four powerful explosive eruptions beginning 1.2 million years ago. The latest of these, about 74,000 years ago, was the world's largest known Quaternary eruption, producing the Young Toba Tuff (YTT). The YTT consists of about 4000 cu km of ashfall- and voluminous pyroclastic-flow deposits, erupted from vents at the NW and SE ends of present-day Lake Toba.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey)
The 35 x 100 km wide Toba caldera, partially filled by waters of Sumatra's Lake Toba, is Earth's largest Quaternary caldera. This view looks west toward the northern end of Samosir Island, which is part of a massive inclined block uplifted after eruption of the Young Toba Tuff (YTT) about 74,000 years ago. The island, once entirely covered by Lake Toba, is formed of caldera-fill deposits of YTT capped by lake sediments.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey)
The steep-sided wall behind Tomok village on Samosir Island is part of a block of uplifted caldera-fill rocks. The entire 630-sq-km island, which now rises to 700 m above Lake Toba, is capped by lake-floor sediments deposited before the island was uplifted above lake level.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey)
Clouds obscure the summit of Pusukbukit, a young stratovolcano constructed on the western margin of Toba caldera. An active hydrothermal area forms the light-colored area at the base of the volcano across a narrow strait from Samosir Island on Lake Toba.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey)
Post-caldera activity at Toba included the construction of Holocene volcanoes along the caldera rim and active hot springs. These terraces at Sipoholon Hot Springs are part of still-active thermal areas located along the western caldera ring fracture and along the west edge of Samosir Island.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey).
Sulfur-encrusted Terraces at Sipoholon Hot Springs on the west-central shore of Lake Toba are part of a number of still-active thermal areas located along Toba's western caldera ring fracture and across a narrow strait along the western edge of Samosir Island.

Photo by Tom Casadevall, 1987 (U.S. Geological Survey)
Majestic 100-km-long Lake Toba is seen from its northern end. The lake fills a massive 100 x 30 km caldera formed during four major late-Pleistocene eruptions. The western caldera scarp forms the cliffs at the right. The low-angle slope on the left horizon is Samosir Island, half of a large resurgent block in the center of the caldera. The 1700-sq-km lake is the largest in SE Asia.

Anonymous photo, 1993.
The eastern wall of Toba caldera forms the horizon across Lake Toba from Samosir Island in the foreground. The small Tuk-Tuk peninsula (center) extends into the lake from the large 630 sq km island. The small conical peak on the horizon at left-center is Tandukbenua volcano, which may have erupted only a few hundred years ago.

Photo by Bill Rose, 1982 (Michigan Technological University).
Sipisupisu waterfall, at the northern end of Lake Toba, plunges over a cliff in the Middle Toba Tuff (MTT). The MTT rhyolitic ignimbrite was emplaced about 500,000 years ago durng the next to smallest of the four major caldera-forming eruptions at Toba. Products of the densely welded >60 cu km MTT eruption are distributed over the northern part of the caldera.

Photo by Bill Rose, 1982 (Michigan Technological University).
Pusukbukit, the most prominent post-caldera volcano at Toba caldera, was constructed just within the western caldera rim. It is seen here across a narrow strait from Samosir Island, with light-colored solfataric areas along its northern flank. The youngest lava flow on 1972-m-high Pusukbukit is of dacitic compostion.

Photo by Mike Dolan, 1993 (Michigan Technological University).
Tuk-Tuk, a small peninsula on Samosir Island, provides a vista of Latung Strait, which separates the opposing resurgent blocks of Samosir Island (right) and the Uluan block on the left. The Latung Strait marks the center of post-caldera resurgence, which tilted the Uluan block, located within the SE part of the caldera, to the SE and the Samosir Island block to the NE.

Photo by Mike Dolan, 1993 (Michigan Technological University).
Weather clouds rise above the summit of Pusukbukit (right), a 1972-m-high post-caldera stratovolcano constructed just inside the western rim of Toba caldera. Lake Toba, which fills the caldera, is visible beyond the northern (left) flank of Pusukbukit. Solfataric areas are located along the lake on the northern flank of Pusukbukit.

Photo by Bill Rose, 1982 (Michigan Technological University).
Toba, the Earth's largest Quaternary caldera, is seen here in a NASA Landsat satellite image (with north to the top). The 35 x 100 km caldera, partially filled by Lake Toba, was formed during four major ignimbrite-forming eruptions in the Pleistocene, the latest of which occurred about 74,000 years ago. The large island of Samosir is a resurgent uplifted block. The solfatarically active Pusukbukit volcano was later constructed near the south-central caldera rim, and Tandukbenua volcano on the NW rim may be only a few hundred years old.

NASA Landsat7 image (worldwind.arc.nasa.gov)

The following references have all been used during the compilation of data for this volcano, it is not a comprehensive bibliography. Discussion of another volcano or eruption (sometimes far from the one that is the subject of the manuscript) may produce a citation that is not at all apparent from the title.

Aldiss D T, Whandoyo R, Ghazali S A, Kusyono, 1983. Geologic map of the Sidikalang and (part of) Sinabang quadrangles, Sumatra. Geol Res Devel Centre Indonesia, 1:250,000 scale map and 41 p text.

Chesner C A, Rose W I, 1991. Stratigraphy of the Toba tuffs and the evolution of the Toba caldera complex, Sumatra, Indonesia. Bull Volc, 53: 343-356.

Clarke M C G, Ghazali S A, Harahap H, Kusyono, Stephenson B, 1982. Geologic map of the Pematangsiantar quadrangle, Sumatra. Geol Res Devel Centre Indonesia, 1:250,000 scale map and 26 p text.

Knight M D, Walker G P L, Ellwood B B, Diehl J F, 1986. Stratigraphy, paleomagnetism, and magnetic fabric of the Toba Tuffs: constraints on the sources and eruptive styles. J Geophys Res, 91: 10,355-10,382.

Neumann van Padang M, 1951. Indonesia. Catalog of Active Volcanoes of the World and Solfatara Fields, Rome: IAVCEI, 1: 1-271.

Newhall C G, Dzurisin D, 1988. Historical unrest at large calderas of the world. U S Geol Surv Bull, 1855: 1108 p, 2 vol.

Rampino M R, Ambrose S H, 2000. Volcanic winter in the Garden of Eden: the Toba supereruption and the late Pleistocene human population crash. In: McCoy R W, Heiken G (eds), {Volcanic Hazards and Disasters in Human Antiquity}, Geol Soc Amer Spec Pap, 345: 71-82.

Rose W I, Chesner C A, 1990. Worldwide dispersal of ash and gases from earth's largest known eruption: Toba, Sumatra, 75 ka. Palaeogeog, Palaeoclimat, Palaeoecol, 89: 269-275.

Volcano Types

Caldera
Stratovolcano
Lava dome(s)

Tectonic Setting

Subduction zone
Continental crust (> 25 km)

Rock Types

Major
Dacite
Rhyolite
Trachyandesite / Basaltic trachy-andesite
Andesite / Basaltic Andesite

Population

Within 5 km
Within 10 km
Within 30 km
Within 100 km
125,908
125,908
168,995
3,437,177

Affiliated Databases

Large Eruptions of Toba Information about large Quaternary eruptions (VEI >= 4) is cataloged in the Large Magnitude Explosive Volcanic Eruptions (LaMEVE) database of the Volcano Global Risk Identification and Analysis Project (VOGRIPA).
WOVOdat WOVOdat is a database of volcanic unrest; instrumentally and visually recorded changes in seismicity, ground deformation, gas emission, and other parameters from their normal baselines. It is sponsored by the World Organization of Volcano Observatories (WOVO) and presently hosted at the Earth Observatory of Singapore.
EarthChem EarthChem develops and maintains databases, software, and services that support the preservation, discovery, access and analysis of geochemical data, and facilitate their integration with the broad array of other available earth science parameters. EarthChem is operated by a joint team of disciplinary scientists, data scientists, data managers and information technology developers who are part of the NSF-funded data facility Integrated Earth Data Applications (IEDA). IEDA is a collaborative effort of EarthChem and the Marine Geoscience Data System (MGDS).
Smithsonian Collections Search the Smithsonian's NMNH Department of Mineral Sciences collections database. Go to the "Search Rocks and Ores" tab and use the Volcano Name drop-down to find samples.