The Great Basin
The Great Basin in the western United States (Great Basin) cordillera
The plateau in the Inland basin. The western Nevada mountains and the Cascade Mountains, east to Wasatch Mountains, north of the Columbia plateau, south of the Colorado plateau. By a series of massive mountains to the north and South (elevation 1800 - 3300 meters) and many basin. At the bottom of the basin elevation 1200 - 1500 meters, the lowest 85 meters below the sea level in the valley. Dry climate, annual rainfall of 100 to 350 mm, rare plants, shrubs to drought. Many saltwater lake. The great lakes large Saline Lake, Pyramid Lake, sevier lake, Utah lake. Is rich in copper, gold, lead, zinc, iron and other minerals. The animal husbandry and agricultural irrigation in Piedmont region.
The Great Basin
The Great Basin The Great Basin
The Great Basin brief introduction
In the western United States in the wilderness, the Great Basin because of its isolation and magical combination of mountains, desert canyon, has attracted more and more attention.
American Explorer John C fremint will desert between California and Utah in the Sierra Nevada ridge named big basin". Because, in the 33.6 square kilometers of the vast flat valley, dry up. Not from the evaporation of water in the desert that shallow lakes, is seeping into the ground.
The Great Basin Natural landscape North America
The strange Natural landscape
That can be smoothly "broad valley to the north and south of the rock cliff mountain massif and the intervening two parts. It covers a piece of about 492000 square kilometers (190000 square miles) of the Western Sierras gally, within the community, east of Wasechi (Wasatch) mountain, north of Columbia south to the Harvey mesa, Mo (Mojave) desert. U.S.A Nevada
Most of the western half of Utah, and part of other nearby states were included in the field. A large desert basin and the Great Basin is sometimes common. The Great Basin is a sub basin and the largest "mountains area", the latter is a topographical landscape, it covers the south of southern arizona, New Mexico
The southeast and central Texas, Western Mexico and northwest tip.
The Great Basin Terrain
In an ancient survey report, the Great Basin mountains were compared to a group of North irregular crawling caterpillar. These range in length from 95 to 190 km (60 to 120 miles) ranging in width from 5 to 24 kilometers (3 to 15 miles) range. The valley is usually slightly wider than the mountains, mostly desert soil at an altitude of 300 to 1800 meters (1000 to 6000 feet). The height of the mountains are usually at 2750 meters (9000 feet) above. To achieve this high mountains can obtain a certain degree of rainfall to maintain the growth of coniferous forest. However, because of the Sierra Nevada on the west side of the barrier, the rain can not reach the Pacific wind caused a large basin, covering the entire area "rain shadow region". Annual rainfall of 254 mm (10 inches) below, except sparse desert or semi desert plants and other plants to grow.
The Great Basin Basin drainage system
The Great Basin especially let people pay attention to the place is inside the drainage system, down to the great basin surface water was finally oriented closed Valley, and not to the sea. For example: Humboldt River
(originated in Nevada Humboldt River, northeast mountain), westward flow together many streams, and finally into the enclosed Humboldt depression. The lowest in the Saline Lake is located in the western Utah basin, it is a collection of many water.
The Great Basin Human exploration
For people who want to cross the border into California, barren Great Basin has been a barrier for a long time, and the development of the western United States has been seriously affected. Western Explorer Smith (Jedediah Smith, 1798 ~ 1831) made across the Great Basin Initiative in 1824, but no record of the journey. Fremont (John C. Fremont) after him in the 1846 survey of the eastern Great Basin area, but not across it. The summer and autumn of 1846, unlucky Tang Na expedition (Donner Party) from the location of Salt Lake City later, along the Humboldt River, crossing to the Sierra Nevada, but on the heels of the winter expedition, almost half of people died in the terrible snow in the Sierra nevada. 1848 to 1849 years, the California gold rush attracted thousands of people in the west, most of them arrived in Salt Lake City, are trying to find various ways across the great basin. 1867 to 1878 years, a survey by the federal government to support the team for the first time in the Utah region of Nevada provides climate and traffic conditions and resources science report.
The Great Basin Landforms
The Great Basin mountains and valleys, huge plots can be regarded by crustal rise and subsidence and tilt the composition. The huge fracture or fault block to uplift, rise in the experience of long-term weathering, become debris dust to cover the sunken part. Between wasai Chishan and the Sierra Nevada, the width of these plots in 24 ~ 48 km (15 to 30 miles), roughly north-south, is about 30.
In many parts of the Great Basin, volcano rock cut or gravel covered fault. The volcano rock age of about 30 million years between the fault occurrence time is more obvious than it is young. Because the fault surface is very new, visible faults are relatively recent thing, due to the earthquake in this area in history record, and still continue to appear small earthquake, visible fault formation and continues to this day on.
The Great Basin mineral resources
As the most important resource of mineral basin, gold, magnesite, barite and mercury are produced in the United States great part of nevada. The main origin of Nevada is lithium, silver, diatomaceous earth and stones. Utah is one of the main origin of beryllium, is a major producer of gold and silver, lead, uranium and molybdenum minerals.
Residents in Utah are mostly in the West foot of wasai Chishan, concentrated in Salt Lake City. Drinking water is the source of mountain streams and wells. Similarly, at the other end of the Great Basin, Nevada residents (mostly in concentrated in the east of the Sierra Nevada Reynolds). The Sierra Nevada provides most of the drinking water for the people in the area.