Tuya Butte is a

tuya A tuya is a flat-topped, steep-sided volcano formed when lava erupts through a thick glacier or ice sheet. They are rare worldwide, being confined to regions which were covered by glaciers and had active volcanism during the same period. As lava ...

in the Tuya Range of north-central

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

, Canada. It is a bit less isolated from other ranges than neighbouring Mount Josephine. Some of the other volcanoes in the area include South Tuya, Ash Mountain, and Mathews Tuya. Tuya Butte was the first tuya analyzed in the geological literature, and its name has since become standard worldwide among

volcanologist A volcanologist, or volcano scientist, is a geologist who focuses on understanding the formation and eruptive activity of volcanoes. Volcanologists frequently visit volcanoes, sometimes active ones, to observe and monitor volcanic eruptions, col ...

s in referring to and writing about tuyas. The Tuya Mountains Provincial Park was recently established to protect this unusual landscape, which lies north of Tuya Lake and south of the Jennings River near the boundary with the Yukon Territory. Tuya Butte is regarded as among the best examples of this landform outside

Iceland Iceland is a Nordic countries, Nordic island country between the Atlantic Ocean, North Atlantic and Arctic Oceans, on the Mid-Atlantic Ridge between North America and Europe. It is culturally and politically linked with Europe and is the regi ...

and

Antarctica Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean (also known as the Antarctic Ocean), it contains the geographic South Pole. ...

. Tuya Butte was named by Canadian

Bill Mathews in association with adjacent Tuya Lake and Butte Lake. The term ''tuya'' may be derived from a

Tahltan The Tahltan or Nahani are a First Nations people of the Athabaskan-speaking ethnolinguistic group who live in northern British Columbia around Telegraph Creek, Dease Lake, and Iskut. The Tahltan constitute the fourth division of the ''Nahan ...

word.

Geology

Tuya Butte is part of the Tuya Volcanic Field, a

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

that includes tuyas, postglacial

lapilli Lapilli (: lapillus) is a size classification of tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts. ''Lapilli'' is Latin for "little stones". By definition lapilli range from in dia ...

cones and lava flows and several small

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 ...

es formed during the

Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

and

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

. This in turn is part of the

Northern Cordilleran Volcanic Province The Northern Cordilleran Volcanic Province (NCVP), formerly known as the Stikine Volcanic Belt, is a geologic province defined by the occurrence of Miocene to Holocene volcanoes in the Pacific Northwest of North America. This belt of volcanoes ex ...

from

Prince Rupert Prince Rupert of the Rhine, Duke of Cumberland, (17 December 1619 ( O.S.) 7 December 1619 (N.S.)– 29 November 1682 (O.S.) December 1682 (N.S) was an English-German army officer, admiral, scientist, and colonial governor. He first rose to ...

, into the

Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...

and the

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

border caused by

rift In geology, a rift is a linear zone where the lithosphere is being pulled apart and is an example of extensional tectonics. Typical rift features are a central linear downfaulted depression, called a graben, or more commonly a half-graben ...

ing of the North American Plate as the Pacific Plate slides northward along the Queen Charlotte Fault. Tuya Butte formed when

magma Magma () is the molten or semi-molten natural material from which all igneous rocks are formed. Magma (sometimes colloquially but incorrectly referred to as ''lava'') is found beneath the surface of the Earth, and evidence of magmatism has also ...

intruded into and melted a vertical pipe in the overlying Cordilleran Ice Sheet. The partially molten mass cooled as a large block, forming the highly developed

hyaloclastite Hyaloclastite is a volcanoclastic accumulation or breccia consisting of glass (from the Greek ''hyalus'') fragments (clasts) formed by quench fragmentation of lava flow surfaces during submarine or subglacial extrusion. It occurs as thin marg ...

and

pillow lava Pillow lavas are lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava underwater, or ''subaqueous extrusion''. Pillow lavas in volcanic rock are characterized by thick sequences of discontinu ...

with gravity flattening its upper surface. Horizontal columns occur at numerous locations along the periphery of the mass. The absence of glacial erosion of the tuya suggests that it erupted during the

. The volcano has no summit crater or obvious vent, suggesting the volcano was fed by a

fissure 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 ...

, although several indictions suggest a vent location near a large cirque on the north face. Other subglacial volcanoes can be found in the

Wells Gray-Clearwater volcanic field The Wells Gray-Clearwater volcanic field, also called the Clearwater Cone Group, is a potentially active monogenetic volcanic field in east-central British Columbia, Canada, located approximately north of Kamloops, British Columbia, Kamloops. It ...

and the

Garibaldi Volcanic Belt The Garibaldi Volcanic Belt is a northwest–southeast trending volcanic chain in the Pacific Ranges of the Coast Mountains that extends from Watts Point in the south to the Ha-Iltzuk Icefield in the north. This chain of volcanoes is located in s ...

References

External links

Volcano World: Tuya Butte
{{Interior Mountains Volcanoes of British Columbia One-thousanders of British Columbia Tuyas of Canada Northern Cordilleran Volcanic Province Stikine Country Stikine Ranges Pleistocene volcanoes Monogenetic volcanoes Buttes Pleistocene British Columbia

Geology

See also

References

External links