Tolbachik (russian: Толбачик) 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 in t ...

on the

Kamchatka Peninsula The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) 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 we ...

in the far east of

Russia Russia (, , ), or the Russian Federation, is a List of transcontinental countries, transcontinental country spanning Eastern Europe and North Asia, Northern Asia. It is the List of countries and dependencies by area, largest country in the ...

. It consists of two volcanoes, Plosky (''flat'') Tolbachik (3,085 m) and Ostry (''sharp'') Tolbachik (3,682 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 warrior's 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 v ...

and a peaked

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 per ...

. 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 In seismology, an earthquake swarm is a sequence of seismic events occurring in a local area within a relatively short period. The time span used to define a swarm varies, but may be days, months, or years. Such an energy release is different f ...

, which led to a successful

prediction A prediction (Latin ''præ-'', "before," and ''dicere'', "to say"), or forecast, is a statement about a future event or data. They are often, but not always, based upon experience or knowledge. There is no universal agreement about the exact ...

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 conical hill of loose pyroclastic fragments, such as volcanic clinkers, volcanic ash, or scoria that has been built around a volcanic vent. The pyroclastic fragments are formed by explosive eruptions o ...

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 moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or un ...

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 A fissure is a long, narrow crack opening along the surface of Earth. The term is derived from the Latin word , which means 'cleft' or 'crack'. Fissures emerge in Earth's crust, on ice sheets and glaciers, and on volcanoes. Ground fissure A ...

. 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
This satellite image
was collected on December 22, 2012. According to th
Kamchatka Volcanic Eruption Response Team (KVERT)
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 A fumarole (or fumerole) is a vent in the surface of the Earth or other rocky planet from which hot volcanic gases and vapors are emitted, without any accompanying liquids or solids. Fumaroles are characteristic of the late stages of volcani ...

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 gravity o ...

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"
{{Authority control Active volcanoes Volcanoes of the Kamchatka Peninsula Mountains of the Kamchatka Peninsula Complex volcanoes Shield volcanoes of Russia Stratovolcanoes of Russia Holocene shield volcanoes Holocene stratovolcanoes Holocene Asia Geological type localities

Activity

Mineralogy

Views

See also

References

Other references