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The Sierra Nevada ( or , , ''snowy range'') is a mountain range in the western United States, between the Central Valley of California and the Basin and Range Province. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily in Nevada. The Sierra runs north-to-south, and is approximately across east-to-west. Notable Sierra features include Lake Tahoe, the largest alpine lake in North America; Mount Whitney at ,〔 the highest point in the contiguous United States; and Yosemite Valley sculpted by glaciers out of one-hundred-million-year-old granite. The Sierra is home to three national parks, twenty wilderness areas, and two national monuments. These areas include Yosemite, Sequoia, and Kings Canyon National Parks; and Devils Postpile National Monument. The character of the range is shaped by its geology and ecology. More than one hundred million years ago during the Nevadan orogeny, granite formed deep underground. The range started to uplift four M.A. (million years) ago, and erosion by glaciers exposed the granite and formed the light-colored mountains and cliffs that make up the range. The uplift caused a wide range of elevations and climates in the Sierra Nevada, which are reflected by the presence of five life zones. Uplift continues due to faulting caused by tectonic forces, creating spectacular fault block escarpments along the eastern edge of the southern Sierra. The Sierra Nevada has a significant history. The California Gold Rush occurred in the western foothills from 1848 through 1855. Due to inaccessibility, the range was not fully explored until 1912.〔 ==Geography== The Sierra Nevada lies in Central and Eastern California, with a very small but historically important spur extending into Nevada. West-to-east, the Sierra Nevada's elevation increases gradually from in the Central Valley to an average height of about at its crest only to the east. The east slope forms the steep Sierra Escarpment. Unlike its surroundings, the range receives a substantial amount of snowfall and precipitation due to orographic lift. Environments at higher elevations from up to the tree line tend to be wet and marshy. Donner Pass is known as one of the snowiest places in the United States. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Sierra Nevada (U.S.)」の詳細全文を読む スポンサード リンク
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