The Chilcotin Plateau is part of the Fraser Plateau, a major subdivision of the Interior Plateau of

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 ...

. The Chilcotin Plateau is physically near-identical with the region of the same name, i.e. "the Chilcotin", which lies between the

Fraser River The Fraser River is the longest river within British Columbia, Canada, rising at Fraser Pass near Blackrock Mountain in the Rocky Mountains and flowing for , into the Strait of Georgia just south of the City of Vancouver. The river's annua ...

and the southern

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 ...

and is defined by the basin of the

Chilcotin River The Chilcotin River /tʃɪlˈkoʊtɪn/ located in Southern British Columbia, Canada is a long tributary of the Fraser River. The name Chilcotin comes from Tŝilhqot’in, meaning "ochre river people," where ochre refers to the mineral used by ...

and so includes montane areas beyond the plateau. East of the Chilcotin Plateau, across the

, is the Cariboo Plateau, while to the north beyond the West Road (Blackwater) River is the Nechako Plateau. West and south of the Chilcotin Plateau are various subdivisions of the

, including the Chilcotin Ranges which lie along the plateau's southwest. Included within the definition of the Chilcotin Plateau are the Rainbow Range, near Bella Coola and the similarly volcanic Ilgachuz Range and Itcha Range both of which are major shield volcanoes. The

Camelsfoot Range The Camelsfoot Range is a sub-range of the Chilcotin Ranges subdivision of the Pacific Ranges of the Coast Mountains in British Columbia. The Fraser River forms its eastern boundary. The range is approximately 90 km at its maximum length and ...

, north of Lillooet, is included in the Chilcotin Plateau by some systems of classification. The plateau is nearly entirely drained by the

and its tributaries, the largest of which are the Chilanko and Chilko Rivers. Also draining the plateau on its eastern edge is Churn Creek, which forms the east flank of the

and enters the

Fraser Fraser may refer to: Places Antarctica * Fraser Point, South Orkney Islands Australia * Fraser, Australian Capital Territory, a suburb in the Canberra district of Belconnen * Division of Fraser (Australian Capital Territory), a former federal ...

directly. On the west side of the plateau, the basins of the Dean, Homathko and Atnarko Rivers penetrate the massifs of the

and have their beginnings, or the early part of their courses, on the Chilcotin Plateau. The Chilcotin Plateau consists of

basalt Basalt (; ) is an aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the surface of a rocky planet or moon. More than 90% of a ...

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 ...

of the Chilcotin Group, a group of related

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 that is nearly parallel with the Fraser Plateau.Chasm and Dog Creek lithofacies, Chilcotin Group basalt, Bonaparte Lake map area, British Columbia
/ref> It extends along the adjacent

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 i ...

in the

. Volcanism of the Chilcotin Plateau is considered to be related to back-arc basin crustal extension behind the coastal Cascadia subduction zone.

References

{{Authority control Interior Plateau Landforms of the Chilcotin Volcanism of British Columbia Lava plateaus Back-arc volcanism Plateaus of British Columbia

See also

References