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Raft River Mountains
The Raft River Mountains are a mountain range in northern Box Elder County, Utah, United States. The mountains are located in the Raft River Division of the Minidoka Ranger District of the Sawtooth National Forest. The highest point is Bull Mountain, near the Dunn Benchmark, at , and the ghost town of Yost is on the north-central slopes. Tributaries of the Raft River drain the northern slopes of the range to the Snake River then Columbia River and Pacific Ocean, while the southern slopes drain to the Great Salt Lake. Geography Located in the Sawtooth National Forest, the range's montane forest ecoregion is "''surrounded by montane steppes and desert''". The range is oriented in an east–west orientation, and is a portion of the Great Basin Divide and the Basin and Range Province between the Bonneville Basin of the Great Basin (south). Geology The central mass of the range consists of Precambrian metamorphic rocks. The Elba Quartzite with interlayered schist outcrops ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bonneville Salt Flats
The Bonneville Salt Flats are a densely packed salt pan in Tooele County in northwestern Utah. A remnant of the Pleistocene Lake Bonneville, it is the largest of many salt flats west of the Great Salt Lake. It is public land managed by the Bureau of Land Management and is known for land speed records at the Bonneville Speedway. Access to the Flats is open to the public. The Flats are about 12 miles (19 km) long and 5 miles (8 km) wide, with a crust almost 5 ft (1.5m) thick at the center and less than one inch (2.5 cm) towards the edges. It is estimated to hold 147 million tons of salt, approximately 90% of which is common table salt. History Geologist Grove Karl Gilbert named the area after Benjamin Bonneville, a U.S. Army officer who explored the Intermountain West in the 1830s. In 1907, Bill Rishel and two local businessmen tested the suitability of the salt for driving by taking a Pierce-Arrow onto its surface. A railway line across the Flats was completed in 1910, ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trailhead
A trailhead is the point at which a trail begins, where the trail is often intended for hiking, biking, horseback riding, or off-road vehicles. Modern trailheads often contain rest rooms, maps, sign posts and distribution centers for informational brochures about the trail and its features, and parking areas for vehicles and trailers. The United States Access Board states "A trailhead is defined as an outdoor space that is designated by an entity responsible for administering or maintaining a trail to serve as an access point to the trail." The intersection of two trails is a trail junction and does not constitute a trailhead. Historically, the cities located at the terminus of major pathways for foot traffic such as the Natchez Trace and the Chisholm Trail were also known as trailheads. For mountain climbing and hiking, the elevation of the trailhead above sea level is posted to give an idea of how high the mountain is above the Height above average terrain, average terrain. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columbia Plateau
The Columbia Plateau is a geologic and geographic region that lies across parts of the U.S. states of Washington, Oregon, and Idaho. It is a wide flood basalt plateau between the Cascade Range and the Rocky Mountains, cut through by the Columbia River. Geology During late Miocene and early Pliocene times, a flood basalt engulfed about of the Pacific Northwest, forming a large igneous province. Over a period of perhaps 10 to 15 million years, lava flow after lava flow poured out, ultimately accumulating to a thickness of more than 6,000 feet (1.8 km). As the molten rock came to the surface, the Earth's crust gradually sank into the space left by the rising lava. The Columbia River Basalt Group consists of seven formations: The Steens Basalt, Imnaha Basalt, Grande Ronde Basalt, Picture Gorge Basalt, Prineville Basalt, Wanapum Basalt, and Saddle Mountains Basalt. Many of these formations are subdivided into formal and informal members and flows. The subsidence of the crust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ecoregion
An ecoregion (ecological region) or ecozone (ecological zone) is an ecologically and geographically defined area that is smaller than a bioregion, which in turn is smaller than a biogeographic realm. Ecoregions cover relatively large areas of land or water, and contain characteristic, geographically distinct assemblages of natural communities and species. The biodiversity of flora, fauna and ecosystems that characterise an ecoregion tends to be distinct from that of other ecoregions. In theory, biodiversity or conservation ecoregions are relatively large areas of land or water where the probability of encountering different species and communities at any given point remains relatively constant, within an acceptable range of variation (largely undefined at this point). Three caveats are appropriate for all bio-geographic mapping approaches. Firstly, no single bio-geographic framework is optimal for all taxa. Ecoregions reflect the best compromise for as many taxa as possible. Se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northern Basin And Range (ecoregion)
The Northern Basin and Range ecoregion is a Level III ecoregion designated by the United States Environmental Protection Agency (EPA) in the U.S. states of Oregon, Idaho, Nevada, Utah, and California. It contains dissected lava plains, rolling hills, alluvial fans, valleys, and scattered mountain ranges in the northern part of the Great Basin. Although arid, the ecoregion is higher and cooler than the Snake River Plain to the north and has more available moisture and a cooler climate than the Central Basin and Range to the south. Its southern boundary is determined by the highest shoreline of Pleistocene Lake Bonneville, which once inundated the Central Basin and Range. The western part of the region is internally drained; its eastern stream network drains to the Snake River system. The valleys support sagebrush steppe or saltbush vegetation. Mollisol soils are common, in contrast to the aridisols of the Central Basin. Juniper-dominated woodland occurs on rugged, stony uplands ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goose Creek Mountains
The Goose Creek Mountains are a mountain range in Box Elder County, Utah. They are also partly in Elko County, Nevada. It is the least topographically prominent In topography, prominence (also referred to as autonomous height, relative height, and shoulder drop in US English, and drop or relative height in British English) measures the height of a mountain or hill's summit relative to the lowest contou ... of Utah's peaks with more than 609.6 ft (2000 ft) of prominence. References Mountain ranges of Utah Mountain ranges of Box Elder County, Utah Mountain ranges of Nevada Mountain ranges of Elko County, Nevada {{Utah-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartzite
Quartzite is a hard, non- foliated metamorphic rock which was originally pure quartz sandstone.Essentials of Geology, 3rd Edition, Stephen Marshak, p 182 Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Pure quartzite is usually white to grey, though quartzites often occur in various shades of pink and red due to varying amounts of hematite. Other colors, such as yellow, green, blue and orange, are due to other minerals. The term ''quartzite'' is also sometimes used for very hard but unmetamorphosed sandstones that are composed of quartz grains thoroughly cemented with additional quartz. Such sedimentary rock has come to be described as orthoquartzite to distinguish it from metamorphic quartzite, which is sometimes called metaquartzite to emphasize its metamorphic origins. Quartzite is very resistant to chemical weathering and often forms ridges and resistant hilltops. The nearly pure silica conte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cambrian
The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million years ago (mya) to the beginning of the Ordovician Period mya. Its subdivisions, and its base, are somewhat in flux. The period was established as "Cambrian series" by Adam Sedgwick, who named it after Cambria, the Latin name for 'Cymru' (Wales), where Britain's Cambrian rocks are best exposed. Sedgwick identified the layer as part of his task, along with Roderick Murchison, to subdivide the large "Transition Series", although the two geologists disagreed for a while on the appropriate categorization. The Cambrian is unique in its unusually high proportion of sedimentary deposits, sites of exceptional preservation where "soft" parts of organisms are preserved as well as their more resistant shells. As a result, our understanding of the Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grouse Creek Mountains
Grouse are a group of birds from the order Galliformes, in the family Phasianidae. Grouse are presently assigned to the tribe Tetraonini (formerly the subfamily Tetraoninae and the family Tetraonidae), a classification supported by mitochondrial DNA sequence studies, and applied by the American Ornithologists' Union, ITIS, International Ornithological Congress, and others. Grouse inhabit temperate and subarctic regions of the Northern Hemisphere, from pine forests to moorland and mountainside, from 83°N (rock ptarmigan in northern Greenland) to 28°N (Attwater's prairie chicken in Texas). Turkeys are closely related to grouse and are also classified in the tribe Tetraonini. The koklass pheasant is also closely allied with them. Description Grouse are heavily built like other Galliformes, such as chickens. They range in length from , and in weight from . Males are larger than females—twice as heavy in the western capercaillie, the largest member of the family. Grouse have f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schist
Schist ( ) is a medium-grained metamorphic rock showing pronounced schistosity. This means that the rock is composed of mineral grains easily seen with a low-power hand lens, oriented in such a way that the rock is easily split into thin flakes or plates. This texture (geology), texture reflects a high content of platy minerals, such as micas, talc, chlorite group, chlorite, or graphite. These are often interleaved with more granular minerals, such as feldspar or quartz. Schist typically forms during regional metamorphism accompanying the process of mountain building (orogeny) and usually reflects a medium Metamorphism#Metamorphic grades, grade of metamorphism. Schist can form from many different kinds of rocks, including sedimentary rocks such as mudstones and igneous rocks such as tuffs. Schist metamorphosed from mudstone is particularly common and is often very rich in mica (a ''mica schist''). Where the type of the original rock (the protolith) is discernible, the schist is us ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metamorphic Rock
Metamorphic rocks arise from the transformation of existing rock to new types of rock in a process called metamorphism. The original rock (protolith) is subjected to temperatures greater than and, often, elevated pressure of or more, causing profound physical or chemical changes. During this process, the rock remains mostly in the solid state, but gradually recrystallizes to a new texture or mineral composition. The protolith may be an igneous, sedimentary, or existing metamorphic rock. Metamorphic rocks make up a large part of the Earth's crust and form 12% of the Earth's land surface. They are classified by their protolith, their chemical and mineral makeup, and their texture. They may be formed simply by being deeply buried beneath the Earth's surface, where they are subject to high temperatures and the great pressure of the rock layers above. They can also form from tectonic processes such as continental collisions, which cause horizontal pressure, friction, and distorti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
