The Andrei Icefield is a large

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 ...

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 Colum ...

in northwestern

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

, Canada. It is located northwest of the community of

Stewart Stewart may refer to: People *Stewart (name), Scottish surname and given name *Clan Stewart, a Scottish clan *Clan Stewart of Appin, a Scottish clan Places Canada *Stewart, British Columbia *Stewart Township, Nipissing District, Ontario (histor ...

Cassiar Land District The Cassiar Land District is a cadastral survey subdivision of the province of British Columbia, Canada, created with rest of those on Mainland British Columbia via the Lands Act of the Colony of British Columbia in 1860. The British Columbia gove ...

. The icefield is the source of many

valley glacier A valley is an elongated low area often running between hills or mountains, which will typically contain a river or stream running from one end to the other. Most valleys are formed by erosion of the land surface by rivers or streams over ...

s, including Hoodoo Glacier and Twin Glacier, which lie at the headwaters of

Hoodoo River The Hoodoo River is a tributary of the Iskut River in the northwest part of the province of British Columbia, Canada, located west of Hoodoo Mountain and the Twin River in Cassiar Land District. From its source in Hoodoo Glacier the Hoodoo River ...

and Twin River, respectively. Between these two glaciers is

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 ...

, a flat-topped

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 ...

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 e ...

. Other glaciers originating from the Andrei Icefield include Andrei Glacier, Porcupine Glacier, Johnson Glacier and Choquette Glacier, the latter of which lies at the headwaters of

Choquette River The Choquette River is a tributary of the Stikine River, flowing west into that river just north of its confluence with the Iskut. The river is named for Alexander "Buck" Choquette, discoverer of the strike which launched the Stikine Gold Rush an ...

. The western end of the Andrei Icefield contains several named

mountain A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. Although definitions vary, a mountain may differ from a plateau in having a limited summit area, and is usually higher t ...

s, including Mount Robertson, Pheno Mountain, Big Mountain, Mount Verrett, Surprise Mountain, Mount Turner, Mount McGrath, Mount Laura, Mount Choquette, Sugarloaf Mountain, Warm Spring Mountain, Middle Mountain, The Knob and Eagle Crag. Underlying the icefield are

Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago (Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period ...

volcanic rock Volcanic rock (often shortened to volcanics in scientific contexts) is a rock formed from lava erupted from a volcano. In other words, it differs from other igneous rock by being of volcanic origin. Like all rock types, the concept of volcan ...

s comprising the

Stikinia Stikinia, or the Stikine terrane, is a terrane in British Columbia, Canada; the largest of the Canadian Cordillera. It formed as an independent, intraoceanic volcanic arc during the Paleozoic and Mesozoic. Stikinia forms the bedrock of numerous v ...

terrane In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its ow ...

Uranium–lead dating Uranium–lead dating, abbreviated U–Pb dating, is one of the oldest and most refined of the radiometric dating schemes. It can be used to date rocks that formed and crystallised from about 1 million years to over 4.5 billion years ago with routi ...

has yielded

crystallization Crystallization is the process by which solid forms, where the atoms or molecules are highly organized into a structure known as a crystal. Some ways by which crystals form are precipitating from a solution, freezing, or more rarely de ...

ages of around 218 to 223 million years. The Andrei Icefield is larger than the

Columbia Icefield The Columbia Icefield is the largest ice field in North America's Rocky Mountains. Located within the Canadian Rocky Mountains astride the Continental Divide along the border of British Columbia and Alberta, Canada, the ice field lies partly ...

in the

Canadian Rockies The Canadian Rockies (french: Rocheuses canadiennes) or Canadian Rocky Mountains, comprising both the Alberta Rockies and the British Columbian Rockies, is the Canadian segment of the North American Rocky Mountains. It is the easternmost par ...

. It is named after the son of Olav Mokievsky-Zubok, a

glaciologist Glaciology (; ) is the scientific study of glaciers, or more generally ice and natural phenomena that involve ice. Glaciology is an interdisciplinary Earth science that integrates geophysics, geology, physical geography, geomorphology, climato ...

who carried out significant glaciological work in the Coast Mountains from the 1960s to the 1970s.

References

Boundary Ranges Ice fields of British Columbia Cassiar Land District {{BritishColumbiaInterior-geo-stub

See also

References