Dating topography of the sierra nevada
These areas protect 15.4% of the Sierra's 63,118 km Logging and grazing are generally allowed on land controlled by these agencies, under federal regulations that balance recreation and development on the land.The California Bighorn Sheep Zoological Area near Mount Williamson in the southern Sierra was established to protect the endangered Sierra Nevada bighorn sheep.The California Geological Survey states that "the northern Sierra boundary is marked where bedrock disappears under the Cenozoic volcanic cover of the Cascade Range." The range is drained on its western slope by the Central Valley watershed, which discharges into the Pacific Ocean at San Francisco.The northern third of the western Sierra is part of the Sacramento River watershed (including the Feather, Yuba, and American River tributaries), and the middle third is drained by the San Joaquin River (including the Mokelumne, Stanislaus, Tuolumne, and Merced River tributaries).West-to-east, the Sierra Nevada's elevation increases gradually from 1,000 feet (300 m) in the Central Valley to an average height of about 10,500 feet (3,200 m) at its crest only 50–75 miles (80–121 km) to the east. Unlike its surroundings, the range receives a substantial amount of snowfall and precipitation due to orographic lift.The Sierra Nevada's irregular northern boundary stretches from the Susan River It is bounded on the west by California's Central Valley and on the east by the Basin and Range Province.The Sierra rises to almost 14,000 feet (4,300 m) with Mount Humphreys near Bishop, California.
The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily in Nevada.
The Sierra Nevada is part of the American Cordillera, a chain of mountain ranges that consists of an almost continuous sequence of such ranges that form the western "backbone" of North America, Central America, South America and Antarctica.