Yukon Plateau

Yukon Plateau

 

a plateau in the northwestern part of North America. The Yukon Plateau, which occupies much of Alaska’s interior and the northwestern part of Canada, borders on the Brooks Range in the north, the Alaska Range and St. Elias Mountains in the south, the Mackenzie Mountains in the east, and the Bering and Chukchi seas in the west. It consists of large massifs that are separated by tectonic troughs. The mountains, which are deeply dissected by rivers, rise to elevations of 1,500–2,000 m; in the west, the floors of the intermontane basins are situated at elevations not exceeding 200 m, and in the southeast, at elevations not exceeding 500 m.

The plateau is composed of ancient, highly metamorphosed rocks with Mesozoic intrusions and sheets of younger volcanic rock. It has deposits of copper, lead, coal, tungsten, and gold. There is a highly branched system of rivers in the basins of the Yukon River (including the Tanana, Koyukuk, Porcupine, and Stewart rivers) and the Kuskokwim River; the rivers form broad meanders in the intermontane basins.

The region has a subarctic, continental climate. The average January temperatures range from −10° to −30°C, and the average July temperatures, from 10° to 15°C; the lowest recorded temperature is –64°C. The annual precipitation is about 300 mm. Permafrost occurs everywhere. Low willow-poplar flood-plain forests grow along the rivers, while coniferous forests of spruce and larch grow on the river terraces and mountain slopes. Above 400 m there is open woodland, which at 600–700 m is replaced by mountain tundra vegetation.

A. V. ANTIPOVA

References in periodicals archive ?
Despite the purportedly common occurrence of grasslands on the central Yukon Plateau, little is known about the plant communities that form the vegetation except that they typically occur on steep southerly slopes.
2004), as well as the core of the central Yukon Plateau.
These areas include the Yukon Plateau (Atlin Lake), the northern Interior Plateau (Nechako Reservoir and Babine and Stuart lakes), the southern Interior Plateau (Okanagan and Shuswap lakes), portions of the Rocky Mountains (Williston and Kinbasket reservoirs) and the Columbia Mountains (Arrow, Kootenay, Duncan and Revelstoke reservoirs).
Table 3 Number of lakes by physiographic region for the Fisheries Lake Inventory Region Number of lakes Alberta Plateau 37 Coast Mountains 309 Coastal Depression 102 Columbia Mountains 105 Insular Mountains 251 Interior Plateau 1,305 Kaska Mountains 69 Liard Lowland 7 Rocky Mountains 223 Skeena Mountains 28 Stikine plateau 47 Yukon plateau 5 Table 4 Largest natural lakes in British Columbia (BC) Lake Surface area Maximum Volume [S.
For those who could survive on the Yukon plateau, fortunes were being made.
2) in a topographic depression between the east and west flanks of the Yukon Plateau (Bostock, 1948).
Telling the mining history of the Yukon plateau through the personality of its participants is the key nature and value of this book.
The presence of glacial overburden and permafrost had a profound influence in the Yukon plateau.
The majority of ice patches described here are located in the Haines Junction-Whitehorse-Carcross area of southern Yukon, within the northerly portion of the Coast Range and adjacent Yukon Plateau.
Aerial surveys were flown within the Coast Range and Yukon Plateau from 1998 to 2003, during the period of maximum melt (from late July to mid August).

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