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Cascade Range - geography.

Publié le 04/05/2013

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Cascade Range - geography. Cascade Range, lofty mountain range of the northwestern United States and southwestern Canada, about 1130 km (about 700 mi) long. The range extends from northern California through Oregon and Washington into British Columbia, Canada. In the U.S. the Cascades lie from about 160 to 240 km (about 100 to 150 mi) inland from the Pacific Ocean. The Cascades form an important climatic divide, with the western slope receiving abundant precipitation but the eastern slopes very little. As a result, the western part of the range is heavily wooded and the eastern section is covered mainly by grass and scrub plants. In the Cascades are many lakes and several large rivers that are harnessed for hydroelectric power. The name of the range is taken from the great cascades of the Columbia River. The highest point in the Cascades is Mount Rainier (4392 m/14,410 ft), in Washington. Other lofty peaks include Mount Shasta (4317 m/14,162 ft) and Lassen Peak (3187 m/10,457 ft), an active volcano, in California; Mount Hood (3426 m/11,239 ft) and Mount Jefferson (3,199 m/10,497 ft), in Oregon; and Mount Adams (3,742 m/12,276 ft) and Mount Baker (3,285 m/10,778 ft), in Washington. The British Columbia section has elevations reaching about 2440 m (about 8000 ft). Mount Saint Helens (2,550 m/8,365 ft), in Washington, erupted in 1980 and 1982. The Cascade Range has had a complicated geologic history. It was formed toward the close of the Pliocene epoch, but later was altered considerably by volcanic action and glaciation. Today the range affords varied opportunities for outdoor recreation, and it has several large parks. Microsoft ® Encarta ® 2009. © 1993-2008 Microsoft Corporation. All rights reserved.

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