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 high ...

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 pro ...

of the

Coast Mountains The Coast Mountains () 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 British Columbia Coast, Coast of British Columbia sout ...

in northwestern

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 located northwest of the community of Stewart in

Cassiar Land District 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 (1858–1866), Colony of British Columb ...

. The icefield is the source of many

valley glacier Glacier morphology, or the form a glacier takes, is influenced by temperature, precipitation, topography, and other factors. The goal of glacial morphology is to gain a better understanding of glaciated landscapes and the way they are shaped. T ...

s, including

Hoodoo Glacier Hoodoo Glacier is a glacier in northwestern British Columbia, Canada, located on the western flank of Hoodoo Mountain. It lies at the headwaters of the Hoodoo River. The glacier originates from the Andrei Icefield. See also *List of glaciers ...

and

Twin Glacier Twin Glacier is a glacier in northwestern British Columbia, Canada, located on the northern and eastern flanks of Hoodoo Mountain. It lies at the headwaters of the Twin River. The glacier originates from the Andrei Icefield. See also *List of ...

, which lie at the headwaters of Hoodoo River and Twin River, respectively. Between these two glaciers is Hoodoo Mountain, a flat-topped

stratovolcano A stratovolcano, also known as a composite volcano, is a typically conical volcano built up by many alternating layers (strata) of hardened lava and tephra. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile with ...

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 ...

. 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 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 ( ; sometimes symbolized 🝈) is a geologic period and system which spans 50.5 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.4 Mya. The Triassic is t ...

volcanic rock Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and me ...

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 ...

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 d ...

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 a process that leads to solids with highly organized Atom, atoms or Molecule, molecules, i.e. a crystal. The ordered nature of a crystalline solid can be contrasted with amorphous solids in which atoms or molecules lack regu ...

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 () 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 part of the Canadian Cordillera, w ...

. 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, clim ...

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