Raikoke (russian: Райкоке, ja, 雷公計島), also spelled Raykoke, is, as of 2019 a Russian uninhabited

volcanic island Geologically, a high island or volcanic island is an island of volcanic origin. The term can be used to distinguish such islands from low islands, which are formed from sedimentation or the uplifting of coral reefs (which have often form ...

near the centre of the

Kuril Islands The Kuril Islands or Kurile Islands (; rus, Кури́льские острова́, r=Kuril'skiye ostrova, p=kʊˈrʲilʲskʲɪjə ɐstrɐˈva; Japanese: or ) are a volcanic archipelago currently administered as part of Sakhalin Oblast in the ...

chain in the

Sea of Okhotsk The Sea of Okhotsk ( rus, Охо́тское мо́ре, Ohótskoye móre ; ja, オホーツク海, Ohōtsuku-kai) is a marginal sea of the western Pacific Ocean. It is located between Russia's Kamchatka Peninsula on the east, the Kuril Islands ...

in the northwest

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contine ...

, distant from the island of Matua. Its name is derived from the

Ainu language Ainu (, ), or more precisely Hokkaido Ainu, is a language spoken by a few elderly members of the Ainu people on the northern Japanese island of Hokkaido. It is a member of the Ainu language family, itself considered a language family isolate ...

, from “hellmouth”.

Geology

Raikoke is roughly circular, with a length of with a width of , and an area of . The island is a

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 p ...

, its lava composed primarily of basalt. The cone rises above a submarine terrace with a depth of to a maximum height of above sea level. The steep-walled crater is wide and deep with

lava flow 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 ...

s extending along the eastern half of the island. The volcano has most recently erupted in 1765, 1778, 1924 and 2019. The 1778 and 1924 Raikoke eruptions were classified on the Volcanic Explosivity Index scale (that ranges from zero to eight) as VEI-4 or greater. For comparison the volcano Anak Krakatoa eruption in 2018 was also rated as a VEI-4 event. The 1778 eruption of Raikoke was the largest of the recent volcanic events destroying the upper third of the island. The only known fatalities from the eruptions was during the 1778 eruption when fifteen were killed from falling lava bombs.

2019 eruption

At approximately 4:03 am, 22 June 2019 it erupted, with a plume of ash and gas reaching between and , passing the

tropopause The tropopause is the atmospheric boundary that demarcates the troposphere from the stratosphere; which are two of the five layers of the atmosphere of Earth. The tropopause is a thermodynamic gradient-stratification layer, that marks the end of ...

and allowing

stratospheric The stratosphere () is the second layer of the atmosphere of the Earth, located above the troposphere and below the mesosphere. The stratosphere is an atmospheric layer composed of stratified temperature layers, with the warm layers of air hi ...

injection of

ash Ash or ashes are the solid remnants of fires. Specifically, ''ash'' refers to all non-aqueous, non- gaseous residues that remain after something burns. In analytical chemistry, to analyse the mineral and metal content of chemical samples, ash ...

and

sulfur dioxide Sulfur dioxide ( IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a toxic gas responsible for the odor of burnt matches. It is released naturally by volcanic ...

Fauna

Raikoke is one of five major

Steller sea lion The Steller sea lion (''Eumetopias jubatus''), also known as the Steller's sea lion and northern sea lion, is a near-threatened species of sea lion in the northern Pacific. It is the sole member of the genus ''Eumetopias'' and the largest of ...

rookeries on the Kuril Islands and in the spring and summer it is home to one of the largest

northern fulmar The northern fulmar (''Fulmarus glacialis''), fulmar, or Arctic fulmar is a highly abundant seabird found primarily in subarctic regions of the North Atlantic and North Pacific oceans. There has been one confirmed sighting in the Southern Hem ...

aggregations on the Kurils; crested and parakeet auklet, pigeon guillemot, and black-legged kittiwake also nest on the island.Kondratyev, A. Y., Litvinenko, N. M., Shibaev, Y. V., Vyatkin, P. S., & Kondratyeva, L. F. (2000)
The breeding seabirds of the Russian Far East
''Seabirds of the Russian Far East'', 37–81. Captain Henry James Snow reported that in 1883 some 15,000

northern fur seal The northern fur seal (''Callorhinus ursinus'') is an eared seal found along the north Pacific Ocean, the Bering Sea, and the Sea of Okhotsk. It is the largest member of the fur seal subfamily ( Arctocephalinae) and the only living species in ...

s inhabited the island. However, by the 1890s only "a few scores" were recorded captured there, almost certainly due to

overexploitation Overexploitation, also called overharvesting, refers to harvesting a renewable resource to the point of diminishing returns. Continued overexploitation can lead to the destruction of the resource, as it will be unable to replenish. The term ap ...

by fur hunters. Currently no fur seals reproduce on Raikoke. Raikoke

History

Raikoke was visited by hunting and fishing parties of the

Ainu Ainu or Aynu may refer to: *Ainu people, an East Asian ethnic group of Japan and the Russian Far East *Ainu languages, a family of languages **Ainu language of Hokkaido **Kuril Ainu language, extinct language of the Kuril Islands **Sakhalin Ainu la ...

, but there was no permanent habitation at the time of European contact. The island appears on an official map showing the territories of

Matsumae Domain The was a Japanese clan that was confirmed in the possession of the area around Matsumae, Hokkaidō as a march fief in 1590 by Toyotomi Hideyoshi, and charged with defending it, and by extension the whole of Japan, from the Ainu "barbarians" ...

, a feudal domain of Edo Japan dated 1644, and these holdings were officially confirmed by the

Tokugawa shogunate The Tokugawa shogunate (, Japanese 徳川幕府 ''Tokugawa bakufu''), also known as the , was the military government of Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in ...

in 1715. It was subsequently claimed by the

Russian Empire The Russian Empire was an empire and the final period of the List of Russian monarchs, Russian monarchy from 1721 to 1917, ruling across large parts of Eurasia. It succeeded the Tsardom of Russia following the Treaty of Nystad, which ended th ...

;

sovereignty Sovereignty is the defining authority within individual consciousness, social construct, or territory. Sovereignty entails hierarchy within the state, as well as external autonomy for states. In any state, sovereignty is assigned to the perso ...

initially passed to Russia under the terms of the

Treaty of Shimoda The Treaty of Shimoda (下田条約, ''Shimoda Jouyaku'') (formally Treaty of Commerce and Navigation between Japan and Russia 日露和親条約, ''Nichi-Ro Washin Jouyaku'') of February 7, 1855, was the first treaty between the Russian Empire, a ...

, but was returned to the

Empire of Japan The also known as the Japanese Empire or Imperial Japan, was a historical nation-state and great power that existed from the Meiji Restoration in 1868 until the enactment of the post-World War II 1947 constitution and subsequent for ...

per the Treaty of Saint Petersburg along with the rest of the Kuril islands. The island was formerly administered as part of Shimushu District of Nemuro Subprefecture of Hokkaidō. After

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

, it came under the control of the

Soviet Union The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

, and is now administered as part of the

Sakhalin Oblast Sakhalin Oblast ( rus, Сахали́нская о́бласть, r=Sakhalínskaya óblast', p=səxɐˈlʲinskəjə ˈobləsʲtʲ) is a federal subject of Russia (an oblast) comprising the island of Sakhalin and the Kuril Islands in the Rus ...

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-eigh ...

Notes

References

Global Volcanism Program

External links

* {{Sea of Okhotsk Islands Active volcanoes Islands of the Sea of Okhotsk Islands of the Russian Far East Stratovolcanoes of Russia Islands of the Kuril Islands Uninhabited islands of Russia Volcanoes of the Kuril Islands Mountains of the Kuril Islands Holocene stratovolcanoes