Mount Wrangell, in

Ahtna The Ahtna (also Ahtena, Atna, Ahtna-kohtaene, or Copper River) are an Alaska Native Athabaskan people of the Athabaskan-speaking ethnolinguistic group. The people's homeland called Atna Nenn', is located in the Copper River area of souther ...

K’ełt’aeni or K’ełedi when erupting, is a massive

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 ...

located in Wrangell-St. Elias National Park and Preserve in southeastern

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U.S., ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...

. The shield rises over above the

Copper River Copper River may refer to several places: *Copper River (Alaska), in the United States * Copper River (British Columbia), a tributary of the Skeena River The Skeena River is the second-longest river entirely within British Columbia, Canada (afte ...

to its southwest. Its volume is over , making it more than twice as massive as

Mount Shasta Mount Shasta ( Shasta: ''Waka-nunee-Tuki-wuki''; Karuk: ''Úytaahkoo'') is a potentially active volcano at the southern end of the Cascade Range in Siskiyou County, California. At an elevation of , it is the second-highest peak in the Cascades ...

in California, the largest

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 ...

by volume in the Cascades. It is part of the

Wrangell Volcanic Field The Wrangell Volcanic Field is a volcanic field stretching from eastern Alaska in the United States to the southwestern Yukon Territory in Canada. The field includes the four highest volcanoes in the United States, Mount Bona, Mount Blackburn, ...

, which extends for more than across

Southcentral Alaska Southcentral Alaska (russian: Юго-Центральная Аляска) is the portion of the U.S. state of Alaska consisting of the shorelines and uplands of the central Gulf of Alaska. Most of the population of the state lives in this regio ...

into the

Yukon Territory Yukon (; ; formerly called Yukon Territory and also referred to as the Yukon) is the smallest and westernmost of Canada's three territories. It also is the second-least populated province or territory in Canada, with a population of 43,964 as ...

Canada Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, covering over , making it the world's second-largest country by tot ...

, and has an eruptive history spanning the time from Pleistocene to Holocene.

Description

Modern Mount Wrangell, built upon the remnants of a mid-

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

volcano, has an eruptive history spanning from 750,000 years ago to minor

phreatic eruption A phreatic eruption, also called a phreatic explosion, ultravulcanian eruption or steam-blast eruption, occurs when magma heats ground water or surface water. The extreme temperature of the magma (anywhere from ) causes near-instantaneous evapo ...

s in 1884.Volcanoes of North America, Wood and Kienle The shield volcano features an ice-filled

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 ...

in diameter at the top of Wrangell's broad summit. The caldera was apparently formed by

subsidence Subsidence is a general term for downward vertical movement of the Earth's surface, which can be caused by both natural processes and human activities. Subsidence involves little or no horizontal movement, which distinguishes it from slope move ...

rather than large explosive eruptions. The caldera is in turn rimmed by three small craters, which often display

fumarolic 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 volc ...

activity with steam plumes that can sometimes be seen from a distance. The main summit is on the north side of the caldera, while the west summit rises to . The summit region above in elevation is over in size. A very large cinder cone, Mount Zanetti, rises nearly above the northwest flank of Wrangell and is the source of some lava flows.Richter ''et al'', pp. 11–13 Mount Wrangell is almost entirely covered by an

icefield An ice field (also spelled icefield) is a mass of interconnected valley glaciers (also called mountain glaciers or alpine glaciers) on a mountain mass with protruding rock ridges or summits. They are often found in the colder climates and highe ...

that persists from year to year. The largest glacier on Wrangell is

Nabesna Glacier Nabesna Glacier is a glacier in the U.S. state of Alaska. Fed by deep snowfall in the Wrangell Mountains, the 53 mile (85 km) long Nabesna is the longest valley glacier in North America and the world's longest interior valley glacier. The gl ...

, the source of the

Nabesna River The Nabesna River (''Naambia Niign'' in Upper Tanana) is a tributary of the Tanana River in the U.S. state of Alaska. Beginning at Nabesna Glacier in the Alaska Range, it flows north-northeast from Wrangell–St. Elias National Park and Prese ...

. Other glaciers on Mount Wrangell include Cheshnina Glacier, Chetaslina Glacier, Chichokna Glacier, Dadina Glacier and Copper Glacier. Wrangell was the first high volcano in the Wrangell range to be climbed. Its summit can be visited by ski-equipped airplane. WrangellZanettiWillowLake

Naming

Mount Wrangell ang-guhlwas named after Russian Admiral

Ferdinand von Wrangel Baron Ferdinand Friedrich Georg Ludwig von Wrangel (russian: Барон Фердина́нд Петро́вич Вра́нгель, tr. ; – ) was a Baltic German explorer and seaman in the Imperial Russian Navy, Honorable Member of the Saint ...

(or Wrangell), governor of

Russian America Russian America (russian: Русская Америка, Russkaya Amerika) was the name for the Russian Empire's colonial possessions in North America from 1799 to 1867. It consisted mostly of present-day Alaska in the United States, but a ...

from 1830 to 1836. The

Ahtna people The Ahtna (also Ahtena, Atna, Ahtna-kohtaene, or Copper River) are an Alaska Native Athabaskan people of the Athabaskan-speaking ethnolinguistic group. The people's homeland called Atna Nenn', is located in the Copper River area of southern ...

call it K'elt'aeni, "the one who controls the weather," with the alternate name Uk'eledi, "the one with smoke on it" when it is active. On some pre-1900 maps Wrangell was labeled as Mount Tillman.

Volcanic activity

Wrangell is the only volcano in the Wrangell Volcanic Field to have had historically recorded eruptions, generally in the form of small steam and ash explosions. Reports of activity have been recorded in 1784 and 1884–85. The 1784 eruption and another stated to have occurred in 1760 are disputed. The 1884-85 eruption was reported by local prospector Jon Bremner. An 1890 report mention a visible glow. Wrangell also occasionally emits ash, which can be seen coating the summit snow. The bulk of the mountain was built by large lava flows from 600,000 to 200,000 years ago. The summit caldera is believed to have collapsed within the last 200,000 years, and may have collapsed 50,000 years ago. Mount Zanetti is about 25,000 years old. The amount of geothermal heat being emitted by Wrangell increased from the 1950s to the 1980s, raising the possibility of a future eruption. The

heat flux Heat flux or thermal flux, sometimes also referred to as ''heat flux density'', heat-flow density or ''heat flow rate intensity'' is a flow of energy per unit area per unit time. In SI its units are watts per square metre (W/m2). It has both a ...

was high enough to melt ice around the craters and create ice caves and small lakes in the north crater, with about 100 million cubic meters of ice melted by 1986. Since then heat output has decreased and ice has reaccumulated.

References

Bibliography

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External links