Великая Бассейновая депрессия Северной Америки

Large depression in western North America

The Great Basin (lang es) is the largest area of contiguous endorheic watersheds, those with no outlets to the ocean, in North America. It spans nearly all of Nevada, much of Utah, and portions of California, Idaho, Oregon, Wyoming, and Baja California. It is noted for both its arid climate and the basin and range topography that varies from the North American low point at Badwater Basin in Death Valley to the highest point of the contiguous United States, less than 100 mile (161 km) away at the summit of Mount Whitney. The region spans several physiographic divisions, biomes, ecoregions, and deserts.

The hydrographic Great Basin contains multiple deserts and ecoregions, each with its own distinctive set of flora and fauna. The Great Basin overlaps four different deserts: portions of the hot Mojave and Colorado (a region within the Sonoran desert) Deserts to the south, and the cold Great Basin and Oregon High Deserts in the north. The deserts can be distinguished by their plants: the Joshua tree and creosote bush occur in the hot deserts, while the cold deserts have neither. The cold deserts are generally higher than the hot and have more even spread of precipitation throughout the year. The climate and flora of the Great Basin are strongly dependent on elevation; as the elevation increases, the temperature decreases and precipitation increases. Because of this, forests can occur at higher elevations. Utah juniper/single leaf pinyon (southern regions) and mountain mahogany (northern regions) form open pinyon juniper woodland on the slopes of most ranges. Stands of limber pine and Great Basin bristlecone pine (Pinus longaeva) can be found in some of the higher ranges. In riparian areas with dependable water cottonwoods (Populus fremontii) and quaking aspen (Populus tremuloides) groves exist. Because the forest ecosystem is distinct from a typical desert, some authorities, such as the World Wildlife Fund, separate the mountains of the Great Basin desert into their own ecoregion: the Great Basin montane forests. Many rare and endemic species occur in this ecoregion, because the individual mountain ranges are isolated from each other. During the Last Glacial Period, the Great Basin was wetter. As it dried during the Holocene epoch, some species retreated to the higher isolated mountains and have high genetic diversity. Mourning dove, western meadowlark, black billed magpie, and common raven are other common bird species. Two endangered species of fish are found in Pyramid Lake: the Cui ui sucker fish (endangered 1967) and the Lahontan cutthroat trout (threatened 1970). Large invertebrates include tarantulas (genus Aphonopelma) and Mormon crickets. Exotic species, including chukar, grey partridge, and Himalayan snowcock, have been successfully introduced to the Great Basin, although the latter has only thrived in the Ruby Mountains. Cheatgrass, an invasive species which was unintentionally introduced, forms a critical portion of their diets. Feral horses (mustangs) and feral burros are highly reproductive, and ecosystem controversial, alien species. Most of the Great Basin is open range and domestic cattle and sheep are widespread.

The Great Basin includes valleys, basins, lakes and mountain ranges of the Basin and Range Province. The basin and range topography is the result of extension and thinning of the lithosphere, which is composed of crust and upper mantle. Extensional environments like the Basin and Range are characterized by listric normal faulting, or faults that level out with depth. Opposing normal faults link at depth producing a horst and graben geometry, where horst refers to the upthrown fault block and graben to the down dropped fault block. Sediment build up over thousands of years filled the down faulted basins between ranges and created relatively flat lacustrine plains from Pleistocene lake beds of the Great Basin. For example, after forming about 32,000 years ago, Lake Bonneville overflowed about 14,500 years ago in the Bonneville Flood through Red Rock Pass and lowered to the "Provo Lake" level (the Great Salt Lake, Utah Lake, Sevier Lake, Rush Lake, and Little Salt Lake remain). Lake Lahontan, Lake Manly, and Lake Mojave were similar Pleistocene lakes.

The Great Basin physiographic section of the Basin and Range Province contains the Great Basin, but extends into eastern Oregon, southern Idaho, and the Colorado River watershed and the northwest corner of Arizona). The Basin and Range region is the product of geological forces stretching the Earth's crust, creating many north–south trending mountain ranges. These ranges are separated by flat valleys or basins. These hundreds of ranges make Nevada the most mountainous state in the country. and Nevada State Route 375 is designated the "Extraterrestrial Highway". The Great Basin is traversed by several rail lines including the Union Pacific Railroad's Overland Route (Union Pacific Railroad) through Reno and Ogden, Feather River Route, Central Corridor and Los Angeles and Salt Lake Railroad.

There has been a succession of indigenous peoples of the Great Basin. Paleo Indian habitation by the Great Basin tribes began as early as 10,000 B. C. Archaeological evidence of habitation sites along the shore of Lake Lahontan date from the end of the ice age when its shoreline was approximately 500 feet (152 m) higher along the sides of the surrounding mountains. The Paleo Indians were mainly hunters and hunted bison, the extinct mammoth, and extinct ground sloth. For housing, since they followed the animals they were hunting, they had no permanent villages. Other tribes in the area included the Ute, Mono, and Northern Paiute. All of the tribes speak a language in the Numic language group. To close a 1951 Indian Claims Commission case, the Western Shoshone Claims Distribution Act of 2004 established the United States payment of $117 million to the Great Basin tribe for the acquisition of 39000 square miles (101,010 km2).

European exploration of the Great Basin occurred during the 18th century Spanish colonization of the Americas. The first immigrant American to cross the Great Basin from the Sierra Nevada was Jedediah Strong Smith in 1827. Peter Skene Ogden of the British Hudson's Bay Company explored the Great Salt Lake and Humboldt River regions in the late 1820s, following the eastern side of the Sierra Nevada to the Gulf of California. Benjamin Bonneville explored the northeast portion during an 1832 expedition. The United States had acquired claims to the territory north of the 42nd parallel via the 1819 Adams–Onís Treaty with Spain and 1846 Oregon Treaty with Britain. The US gained claims to most of the rest of the Great Basin via the 1848 Mexican Cession. The first non indigenous settlement was in 1847 in the Great Salt Lake Valley, leading to the first American religious settlement effort of the Mormon provisional State of Deseret in 1849 in present day Utah and northern Nevada. Later settlements were connected with the eastern regions of the 1848 California Gold Rush, with its immigrants crossing the Great Basin on the California Trail along Nevada's Humboldt River to Carson Pass in the Sierras. The Oregon Territory was established in 1848 and the Utah Territory in 1850. In 1869 the First transcontinental railroad was completed at Promontory Summit in the Great Basin. Around 1902, the San Pedro, Los Angeles and Salt Lake Railroad was constructed in the lower basin and Mojave Desert for California Nevada rail service to Las Vegas, Nevada.