Tolbachik () is a

volcanic complex A complex volcano, also called a compound volcano or a volcanic complex, is a mixed landform consisting of related volcanic centers and their associated lava flows and pyroclastic rock. They may form due to changes in eruptive habit or ...

on the

Kamchatka Peninsula The Kamchatka Peninsula (, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and western coastlines, respectively. Immediately offshore along the Pacific ...

in the far east of

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

. It consists of two volcanoes, Plosky (''flat'') Tolbachik (3,085 m) and Ostry (''sharp'') Tolbachik (3,672 m), which as the names suggest are respectively a flat-topped

shield volcano A shield volcano is a type of volcano named for its low profile, resembling a shield lying on the ground. It is formed by the eruption of highly fluid (low viscosity) lava, which travels farther and forms thinner flows than the more viscous lava ...

and a peaked

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

. As Ostry is the mountain's highest point, the entire mountain is often referred to as "Ostry Tolbachik", not to be confused with Ostry, a separate volcano to the north also on the Kamchatka Peninsula.

Activity

Its eruptive history stretches back thousands of years, but the most notable eruption occurred in 1975, commonly known as "The Great Tolbachik Fissure Eruption". It was preceded by an earthquake swarm, which led to a successful

prediction A prediction (Latin ''præ-'', "before," and ''dictum'', "something said") or forecast is a statement about a future event or about future data. Predictions are often, but not always, based upon experience or knowledge of forecasters. There ...

of the eruption by scientists from the Russian Institute of Volcanology. The eruption created several new

cinder cone A cinder cone or scoria cone is a steep, volcanic cone, conical landform of loose pyroclastic rock, pyroclastic fragments, such as volcanic ash, clinkers, or scoria that has been built around a volcanic vent. The pyroclastic fragments are forme ...

s, and in terms of volume of

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 Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fractu ...

emitted, was Kamchatka's largest

basalt Basalt (; ) is an aphanite, 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 planetary surface, surface of a terrestrial ...

ic eruption in historic times. On November 27, 2012 a strombolian type eruption started from two fissures. Basaltic lava flows move relatively fast, and quickly flooded buildings 4 km away. The eruption continued for more than a month, as lava continued to flow from the fissures.Volynets A. O., Melnikov D. V., Yakushev A. I. (2013
First data on composition of the volcanic rocks of the IVS 50th anniversary Fissure Tolbachik eruption (Kamchatka)
// Doklady Earth Sciences. V. 452, № 1. P. 953-957. doi: 10.1134/S1028334X13090201. Lava flowed up to 20 kilometers (12 miles) from the line of fissures on the volcano's southern flank. According to the Kamchatka Volcanic Eruption Response Team, the eruption ended September 15, 2013. Several

lava cave A lava cave is any cave formed in volcanic rock, though it typically means caves formed by volcanic processes, which are more properly termed volcanic caves. Sea caves, and other sorts of erosional and crevice caves, may be formed in volcanic rock ...

s were formed as a result of the 2012–2013 eruption.

Mineralogy

The fumarole deposits of Tolbachik are rich in exotic minerals and, , 100 new minerals have been first described here including

alarsite Alarsite (AlAsO4) is an aluminium arsenate mineral with its name derived from its composition: aluminium and arsenate. It occurs as brittle subhedral grains which exhibit trigonal symmetry. It has a Mohs hardness of 5-5.5 and a specific gravit ...

and tolbachite.

Views

Tolbachik Kamchatka from SSW on 2015-07-26

Tolbachik volcano 1975 cone pano Kamchatka on 2015-07-28

ISS-38 Kliuchevskoi Volcano on Kamchatka

References

Other references

*
Plosky Tolbachik volcano and Tolbachik lava field
* Fedotov S.A. and Markhinin Ye.K. (Eds) (1983). ''The Great Tolbachik Fissure Eruption: Geological and Geophysical Data, 1975-1976''. Cambridge University Press, 341 p.

on author's project website
"Russia Begins Here"

External links

Satellite photo of 2012 eruption
taken by Earth Observing-1 at

NASA Earth Observatory NASA Earth Observatory is an online publishing outlet for NASA which was created in 1999. It is the principal source of satellite imagery and other scientific information about the climate and the environment which are being provided by NASA for ...