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The Sierra Nevada is a tilted fault block nearly 400 miles long. Its east face is a high, rugged multiple scarp, contrasting with the gentle western slope (about 2° ) that disappears under sediments of the Central Valley. Deep river canyons are cut into the western slope. Their upper courses, especially in massive granites of the higher Sierra, are modified by glacial sculpturing, forming such scenic features as Yosemite and Hetch Hetchy valleys. The high crest culminates in Mt. Whitney with an elevation of 14,495 feet above sea level near the eastern scarp. The metamorphic bedrock (still partly capped by Tertiary volcanics), contains gold-bearing quartz veins of the Mother Lode system; a north-south structural trend is predominant in the western flank and northern end of the Sierra. The northern Sierra boundary is marked where bedrock disappears under the Cenozoic volcanic cover of the Cascade Range and Modoc Plateau.

Although famous for its rugged mountain landscapes, national parks, and resorts, the Sierra’s principal significance to California’s people is its extensive winter snowfields at elevations above 5,000 feet elevation. It is from the melting of this white winter precipitation during the spring and summer that feeds most of the state’s economically significant streams. These include the Feather, Yuba, Bear, American, Cosumnes, Mokelumne, Stanislaus, Tuolumne, Merced, San Joaquin, Kings, Kaweah, Tule, and Kern rivers flowing westward down into the Central Valley and the Truckee (Lake Tahoe), Walker, and Owens rivers east of the divide. It is their seasonal flow that brings life to the state’s major agricultural areas and cities.


A collection of unique aerial panoramas of this region may be seen in the Sierra Nevada section of the California Atlas of Panoramic Aerial Images.