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Gunnison River
The Gunnison River is located in western Colorado, United States and is one of the largest tributaries of the Colorado River. Description The river flows east to west and has a drainage area of according to the USGS. The drainage basin of the Gunnison collects water from different habitats, such as forests and alpine meadows, located the along Continental Divide. As the river flows westward, it carves through the San Juan Mountains. It flows into the Colorado River at Grand Junction. The Gunnison River Basin is popular for recreational activities such as fishing, rafting, boating, camping, hiking, and rock climbing. Contamination of the Gunnison River with selenium and mercury results from irrigation of high-selenium soils derived from the Mancos Shale and from mineral mining. The region surrounding the Gunnison River is part of the Colorado Mineral Belt. Contamination of the Gunnison River with selenium and mercury is a conservation concern for the bonytail chub, Colora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Canyon Of The Gunnison National Park
Black Canyon of the Gunnison National Park is an American national park located in western Colorado and managed by the National Park Service. There are two primary entrances to the park: the south rim entrance is located east of Montrose, while the north rim entrance is south of Crawford and is closed in the winter. The park contains of the long Black Canyon of the Gunnison River. The national park itself contains the deepest and most dramatic section of the canyon, but the canyon continues upstream into Curecanti National Recreation Area and downstream into Gunnison Gorge National Conservation Area. The canyon's name owes itself to the fact that parts of the gorge only receive 33 minutes of sunlight a day, according to ''Images of America: The Black Canyon of the Gunnison''. In the book, author Duane Vandenbusche states, "Several canyons of the American West are longer and some are deeper, but none combines the depth, sheerness, narrowness, darkness, and dread of the Black Ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North Fork Gunnison River
The North Fork Gunnison River (locally known as the North Fork) is a tributary of the Gunnison River, long,U.S. Geological Survey. National Hydrography Dataset high-resolution flowline dataThe National Map accessed March 18, 2011 in southwestern Colorado in the United States. It drains part of the southwestern flank of the Elk Mountains northeast of Delta. It is formed in the mountains of northwestern Gunnison County by the confluence of Muddy Creek and Anthracite Creek. The confluence is located along State Highway 133 on the south side of McClure Pass. It descends to the southwest through a widening valley past Somerset, Paonia, and Hotchkiss. It joins the Gunnison in eastern Delta County downstream from the Black Canyon between Delta and Hotchkiss. The valley of the river, called the North Fork Valley, has a temperate climate that has historically been a center of fruit growing in southwestern Colorado. It is also a regional center of the coal mining industry, centered on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Habitat
Critical habitat is a habitat area essential to the conservation of a listed species, though the area need not actually be occupied by the species at the time it is designated. This is a specific term and designation within the U.S. Endangered Species Act-ESA. Contrary to common belief, designating an area as critical habitat does not preclude that area from development. Rather, a critical habitat designation affects only federal agency actions. Such actions include federally funded activities or activities requiring a federal permit. Designation process Critical habitat must be designated for all threatened species and endangered species under the Endangered Species Act, with certain specified exceptions. Designations of critical habitats must be based on the best scientific information available and in an open public process within specific timeframes. Unless deemed necessary for the species' continued existence, critical habitat do not include the entire geographical area occup ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Razorback Sucker
The razorback sucker (''Xyrauchen texanus'') is a suckerfish found in rivers and lakes in the southwestern United States. It can grow to in length and is recognisable by the keel between its head and dorsal fin. It used to inhabit much of the Colorado River Basin but commercial fishing, river damming, habitat loss, and predation by nonnative fishes have caused great declines in populations. It is now restricted to the Colorado River upstream of the Grand Canyon and to four reservoirs, Lake Mead, Lake Mohave, Lake Havasu, and Lake Powell. It usually moves from deep water to suitable spawning grounds to breed, and research into its habits and breeding locations is ongoing. It has been a federally protected fish since 1991 and is rated as " critically endangered" by the International Union for Conservation of Nature. There are some signs of recovery, with fish being observed in the lower Grand Canyon in 2012 and 2013. Description The razorback sucker is most notable for the shar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humpback Chub
The humpback chub (''Gila cypha'') is a federally protected fish that lived originally in fast waters of the Colorado River system in the United States. This species takes its name from the prominent hump between the head and dorsal fin, which is thought to direct the flow of water over the body and help maintain body position in the swift currents of the Colorado. The body is almost entirely scaleless, retaining only about 80 mid-lateral scales along the lateral line. The fish is very streamlined, with a thin caudal peduncle and a deeply forked tail. The back is a light olive gray, the sides silver, and the belly white. The dorsal fin usually has nine rays, and the anal fin 10 or more. Maximum recorded length is 38 cm. The humpback chub mostly consumes invertebrates and, to a lesser extent, other fish. They feed at all levels from the bottom to the surface. The species spawns from April through June, at water temperatures of 19-21 °C. The males develop nuptial tuberc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado Pikeminnow
The Colorado pikeminnow (''Ptychocheilus lucius'', formerly squawfish) is the largest cyprinid fish of North America and one of the largest in the world, with reports of individuals up to 6 ft (1.8 m) long and weighing over 100 pounds (45 kg). Native to the Colorado River Basin of the southwestern United States and adjacent Mexico, it was formerly an important food fish for both Native Americans and European settlers. Once abundant and widespread in the basin, its numbers have declined to the point where it has been extirpated from the Mexican part of its range and was listed as endangered in the US part in 1967, a fate shared by the three other large Colorado Basin endemic fish species: bonytail chub, humpback chub, and razorback sucker. The Colorado pikeminnow is currently listed as vulnerable by the IUCN, while its NatureServe conservation status is "critically imperiled". Description Like the other three species of pikeminnows, it has an elongated bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bonytail Chub
The bonytail chub or bonytail (''Gila elegans'') is a cyprinid freshwater fish native to the Colorado River basin of Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming in the southwestern United States; it has been extirpated from the part of the basin in Mexico. It was once abundant and widespread in the basin, its numbers and range have declined to the point where it has been listed as endangered since 1980 (ESA) and 1986 (IUCN), a fate shared by the other large Colorado basin endemic fish species like the Colorado pikeminnow, humpback chub, and razorback sucker. It is now the rarest of the endemic big-river fishes of the Colorado River. There are 20 species in the genus '' Gila'', seven of which are found in Arizona. Description A bonytail chub can grow to long. Like many other desert fishes, its coloring tends to be darker above and lighter below, serving as a camouflage. Breeding males have red fin bases. They have a streamlined body and a terminal mouth. B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado Mineral Belt
The Colorado Mineral Belt (CMB) is an area of ore deposits from the La Plata Mountains in Southwestern Colorado to near the middle of the state at Boulder, Colorado and from which over 25 million troy ounces (778 t) of gold were extracted beginning in 1858. The belt is a "northeast-striking zone defined by: a Proterozoic shear zone system (McCoy, 2001); a suite of Laramide-aged plutons and related ore deposits ( Tweto and Sims, 1963); a major gravity low (Isaacson and Smithson, 1976); low- crustal velocities; and high heat flow (Decker et al., 1988)." Mining districts includ *Central City-Idaho Springs district *Leadville mining district, named for Leadville, Colorado * Sneffels-Red Mountain-Telluride district The belt lies within a zone that has been geologically active at intervals beginning from near the time of crustal accretion in central Colorado at least 1.6 billion years ago until the present. Parts of the CMB follow shear zones of Precambrian age and the Paleozoic an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mancos Shale
The Mancos Shale or Mancos Group is a Late Cretaceous (Upper Cretaceous) geologic formation of the Western United States. The Mancos Shale was first described by Cross and Purington in 1899 and was named for exposures near the town of Mancos, Colorado. Geology The unit is dominated by mudrock that accumulated in offshore and marine environments of the Cretaceous North American Inland Sea. The Mancos was deposited during the Cenomanian (locally Albian) through Campanian ages, approximately from 95 million years ago ( Ma) to 80 Ma. Stratigraphically the Mancos Shale fills the interval between the Dakota and the Mesaverde Group. The lower marine Mancos Shale conformably intertongues with terrestrial sandstones and mudstones of the Dakota and in its upper part grades into and intertongues with the Mesaverde Group. The shale tongues typically have sharp basal contacts and gradational upper contacts. Whereas in the plains east of the Rocky Mountains certain mappable marine sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver and was formerly named hydrargyrum ( ) from the Greek words, ''hydor'' (water) and ''argyros'' (silver). A heavy, silvery d-block A block of the periodic table is a set of elements unified by the atomic orbitals their valence electrons or vacancies lie in. The term appears to have been first used by Charles Janet. Each block is named after its characteristic orbital: s-blo ... element, mercury is the only metallic element that is known to be liquid at standard temperature and pressure; the only other element that is liquid under these conditions is the halogen bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature. Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide). The red pigment vermilion is obtained by Mill (grinding), grinding natural cinnabar or synthetic mercuric sulfide. Mercury is used in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selenium
Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, and also has similarities to arsenic. It seldom occurs in its elemental state or as pure ore compounds in the Earth's crust. Selenium – from Greek ( 'Moon') – was discovered in 1817 by , who noted the similarity of the new element to the previously discovered tellurium (named for the Earth). Selenium is found in metal sulfide ores, where it partially replaces the sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores, most often during production. Minerals that are pure selenide or selenate compounds are known but rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells. Applications in electronics, once important, have been ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
San Juan Mountains
The San Juan Mountains is a high and rugged mountain range in the Rocky Mountains in southwestern Colorado and northwestern New Mexico. The area is highly mineralized (the Colorado Mineral Belt) and figured in the gold and silver mining industry of early Colorado. Major towns, all old mining camps, include Creede, Lake City, Silverton, Ouray, and Telluride. Large scale mining has ended in the region, although independent prospectors still work claims throughout the range. The last large scale mines were the Sunnyside Mine near Silverton, which operated until late in the 20th century and the Idarado Mine on Red Mountain Pass that closed down in the 1970s. Famous old San Juan mines include the Camp Bird and Smuggler Union mines, both located between Telluride and Ouray. The Summitville mine was the scene of a major environmental disaster in the 1990s when the liner of a cyanide-laced tailing pond began leaking heavily. Summitville is in the Summitville caldera, one of m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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