The Iskut volcanic field is a group of

volcano A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates are ...

es and

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 ...

flows on and adjacent to the

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., ...

–

British Columbia British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...

border in the

Boundary Ranges The Boundary Ranges, also known in the singular and as the Alaska Boundary Range, are the largest and most northerly subrange of the Coast Mountains. They begin at the Nass River, near the southern end of the Alaska Panhandle in the Canadian p ...

of the

Coast Mountains The Coast Mountains (french: La chaîne Côtière) are a major mountain range in the Pacific Coast Ranges of western North America, extending from southwestern Yukon through the Alaska Panhandle and virtually all of the Coast of British Columbia ...

. All the volcanoes in this

volcanic field A volcanic field is an area of Earth's crust that is prone to localized volcanic activity. The type and number of volcanoes required to be called a "field" is not well-defined. Volcanic fields usually consist of clusters of up to 100 volcanoes ...

are situated in British Columbia along the

Iskut Iskut is a small, mostly Indigenous community in the Stikine Country of northwestern British Columbia. It is located on Highway 37, at the north end of Eddontenajon Lake just south of Dease Lake and the crossing of the Stikine River. Communit ...

and Unuk rivers and their

tributaries A tributary, or affluent, is a stream or river that flows into a larger stream or main stem (or parent) river or a lake. A tributary does not flow directly into a sea or ocean. Tributaries and the main stem river drain the surrounding drainage b ...

, with lava flows having reached Alaska. The oldest volcanoes in the Iskut volcanic field are

Little Bear Mountain Little Bear Mountain is a basaltic Pleistocene age tuya in the Boundary Ranges of the Coast Mountains that adjoins Hoodoo Mountain to the north. Little Bear Mountain is part of the Northern Cordilleran Volcanic Province. See also * List of volcan ...

and

Hoodoo Mountain Hoodoo Mountain, sometimes referred to as Hoodoo Volcano, is a potentially active stratovolcano in the Northern Interior of British Columbia, Canada. It is located northeast of the Alaska–British Columbia border on the north side of the Isk ...

, which are 146,000 and 85,000 years old, respectively. Younger volcanic centres include Second Canyon, King Creek, Tom MacKay Creek, Snippaker Creek, Iskut Canyon, Cone Glacier,

Cinder Mountain Cinder Mountain is a partly eroded cinder cone at the head of Snippaker Creek, British Columbia, Canada. It is one of the Iskut-Unuk River Cones and is the source of a basaltic lava flow that extends north into Copper King Creek. An isolated ...

and Lava Fork, all of which formed in the last 70,000 years. All of the volcanoes are

mafic A mafic mineral or rock is a silicate mineral or igneous rock rich in magnesium and iron. Most mafic minerals are dark in color, and common rock-forming mafic minerals include olivine, pyroxene, amphibole, and biotite. Common mafic rocks include ...

in composition except for Hoodoo Mountain which consists of

peralkaline rock Peralkaline rocks include those igneous rocks which have a deficiency of aluminium such that sodium and potassium are in excess of that needed for feldspar. The presence of aegerine (sodium pyroxene) and riebeckite (sodium amphibole) are indicative ...

s. The latest volcanic eruption took place from the Lava Fork volcano in 1800, although an uncertain 1904 eruption is also attributed to this volcano. The name Iskut-Unuk River Cones is a nearly synonymous term for this volcanic field but it omits Hoodoo Mountain and Little Bear Mountain, the oldest volcanoes comprising the Iskut volcanic field. The name for this area in the Tlingit language is Séxkhulé, referring to the time of Aan Galakhú (the World Flood) when people took refuge here from the rising flood waters.

References

External links

Catalogue of Canadian volcanoes: Iskut River

Alaska Volcano Observatory: Iskut-Unuk River Cones
Volcanic fields of Canada Boundary Ranges Stikine Country Northern Cordilleran Volcanic Province {{BritishColumbiaInterior-geo-stub