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Antecedent Drainage Stream
An antecedent stream is a stream that maintains its original course and pattern despite the changes in underlying rock topography. A stream with a dendritic drainage pattern, for example, can be subject to slow tectonic uplift. However, as the uplift occurs, the stream erodes through the rising ridge to form a steep-walled gorge. The stream thus keeps its dendritic pattern even though it flows over a landscape that will normally produce a trellis drainage pattern.Grotzinger, J. & Jordan, T.H. 2006. Understanding Earth, 5th ed., Freeman, New York A superimposed stream is a stream that forms over horizontal beds that overlie folded and faulted rock with varying resistance. Having cut down through the horizontal beds, the stream retains its course and pattern as it proceeds to erode the underlying rocks despite their different character. The stream erodes a gorge in the resistant bed and continues its flow as before. Examples * Many Himalayan rivers are good examples of anteced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drainage System (geomorphology)
In geomorphology, drainage systems, also known as river systems, are the patterns formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land. Geomorphologists and hydrologists often view streams as part of drainage basins (and sub-basins). This is the topographic region from which a stream receives runoff, throughflow, and its saturated equivalent, groundwater flow. The number, size, and shape of the drainage basins varies and the larger and more detailed the topographic map, the more information is available. Drainage patterns Per the lie of channels, drainage systems can fall into one of several categories, known as drainage patterns. These depend on the topography and geology of the land. All forms of transitions can occur between parallel, dendritic, and trellis patterns. Accordant versus discordant drainage patterns A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grand Canyon
The Grand Canyon (, yuf-x-yav, Wi:kaʼi:la, , Southern Paiute language: Paxa’uipi, ) is a steep-sided canyon carved by the Colorado River in Arizona, United States. The Grand Canyon is long, up to wide and attains a depth of over a mile (). The canyon and adjacent rim are contained within Grand Canyon National Park, the Kaibab National Forest, Grand Canyon–Parashant National Monument, the Hualapai Indian Reservation, the Havasupai Indian Reservation and the Navajo Nation. President Theodore Roosevelt was a major proponent of the preservation of the Grand Canyon area and visited it on numerous occasions to hunt and enjoy the scenery. Nearly two billion years of Earth's geological history have been exposed as the Colorado River and its tributaries cut their channels through layer after layer of rock while the Colorado Plateau was uplifted. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Gap (geographical Feature)
A wind gap (or air gap) is a gap through which a waterway once flowed that is now dry as a result of stream capture. A water gap is a similar feature, but one in which a waterway still flows. Water gaps and wind gaps often provide routes which, due to their gently inclined profile, are suitable for trails, roads, and railroads through mountainous terrain. Examples of wind gaps in the Blue Ridge Mountains of Virginia include Swift Run Gap, Rockfish Gap, and Buford's Gap. The last was the original crossing of the Blue Ridge Mountains near Bedford for the Virginia and Tennessee Railroad, later the Norfolk and Western Railway, a precursor of today's Norfolk Southern Railway system. Another wind gap with substantial importance in U.S. history is the Cumberland Gap near the junction of Kentucky, Virginia, and Tennessee. Gallery Rockfish Gap November 2009.jpg, Wind gap Rockfish Gap, Blue Ridge Mountains, Virginia Desfiladero C Encantada.jpg, Wind gap opened by an ancient stream ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Gap
A water gap is a gap that flowing water has carved through a mountain range or mountain ridge and that still carries water today. Such gaps that no longer carry water currents are called wind gaps. Water gaps and wind gaps often offer a practical route for road and rail transport to cross the mountain barrier. Geology A water gap is usually an indication of a river that is older than the current topography. The likely occurrence is that a river established its course when the landform was at a low elevation, or by a rift in a portion of the crust of the earth having a very low stream gradient and a thick layer of unconsolidated sediment. In a hypothetical example, a river would have established its channel without regard for the deeper layers of rock. A later period of uplift would cause increased erosion along the riverbed, exposing the underlying rock layers. As the uplift continued, the river, being large enough, would continue to erode the rising land, cutting t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ardennes
The Ardennes (french: Ardenne ; nl, Ardennen ; german: Ardennen; wa, Årdene ; lb, Ardennen ), also known as the Ardennes Forest or Forest of Ardennes, is a region of extensive forests, rough terrain, rolling hills and ridges primarily in Belgium and Luxembourg, extending into Germany and France. Geologically, the range is a western extension of the Eifel; both were raised during the Givetian age of the Devonian (382.7 to 387.7 million years ago), as were several other named ranges of the same greater range. The Ardennes proper stretches well into Germany and France (lending its name to the Ardennes department and the former Champagne-Ardenne region) and geologically into the Eifel (the eastern extension of the Ardennes Forest into Bitburg-Prüm, Germany); most of it is in the southeast of Wallonia, the southern and more rural part of Belgium (away from the coastal plain but encompassing more than half of the country's total area). The eastern part of the Ardennes forms t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meuse (river)
The Meuse ( , , , ; wa, Moûze ) or Maas ( , ; li, Maos or ) is a major European river, rising in France and flowing through Belgium and the Netherlands before draining into the North Sea from the Rhine–Meuse–Scheldt delta. It has a total length of . History From 1301 the upper Meuse roughly marked the western border of the Holy Roman Empire with the Kingdom of France, after Count Henry III of Bar had to receive the western part of the County of Bar (''Barrois mouvant'') as a French fief from the hands of King Philip IV. In 1408, a Burgundian army led by John the Fearless went to the aid of John III against the citizens of Liège, who were in open revolt. After the battle which saw the men from Liège defeated, John ordered the drowning in the Meuse of suspicious burghers and noblemen in Liège. The border remained stable until the annexation of the Three Bishoprics Metz, Toul and Verdun by King Henry II in 1552 and the occupation of the Duchy of Lorraine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Devil's Gate (Wyoming)
Devil's Gate or Devils Gate''Independence Rock, Wyoming,'' 7.5 Minute Topographic Quadrangle, USGS, 1981 is a natural rock formation, a gorge on the Sweetwater River in Wyoming, United States, southwest of Independence Rock. Although the actual route of travel did not pass through the narrow cleft, the site was a major landmark on the Oregon and Mormon trails, and is particularly significant in the history of the latter. Once the Union Pacific Railroad was extended to Benton, six miles east of present-day Sinclair, Wyoming, the Mormon Trail was rerouted through Whiskey Gap in Carbon County, to a point 10 miles west of Devil's Gate to rejoin the original trail. Devil's Gate is a remarkable example of superposed or an antecedent drainage stream. The Sweetwater River cuts a narrow 100-meter deep slot through a granite ridge, yet had it flowed less than a kilometer to the south, it could have bypassed the ridge completely. The gorge was cut because the landscape was originall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paradox Valley
Paradox Valley is a basin located in Montrose County in the U.S. state of Colorado. The dry, sparsely populated valley is named after the apparently paradoxical course of the Dolores River—instead of flowing down the length of the valley, the river cuts across the middle. The valley is the site of a Bureau of Reclamation salinity-control project which has caused thousands of earthquakes, and is the proposed location of a new uranium mill which would be the first built in the United States in over 25 years. Geography and climate Paradox Valley trends northwest-southeast and measures about wide and long. It lies along the extreme western edge of Colorado, about south of the city of Grand Junction. The La Sal Range of Utah rises in the northwest. State Highway 90 follows Paradox Valley on its way from Naturita to the Utah state line, crossing the Dolores River Bridge near the small unincorporated town of Bedrock. The town of Paradox lies a few miles north of the highway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado Plateau
The Colorado Plateau, also known as the Colorado Plateau Province, is a physiographic and desert region of the Intermontane Plateaus, roughly centered on the Four Corners region of the southwestern United States. This province covers an area of 336,700 km2 (130,000 mi2) within western Colorado, northwestern New Mexico, southern and eastern Utah, northern Arizona, and a tiny fraction in the extreme southeast of Nevada. About 90% of the area is drained by the Colorado River and its main tributaries: the Green, San Juan, and Little Colorado. Most of the remainder of the plateau is drained by the Rio Grande and its tributaries. The Colorado Plateau is largely made up of high desert, with scattered areas of forests. In the south-west corner of the Colorado Plateau lies the Grand Canyon of the Colorado River. Much of the Plateau's landscape is related to the Grand Canyon in both appearance and geologic history. The nickname "Red Rock Country" suggests the brightly colored ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colorado River
The Colorado River ( es, Río Colorado) is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and northern Mexico. The river drains an expansive, arid watershed that encompasses parts of seven U.S. states and two Mexican states. The name Colorado derives from the Spanish language for "colored reddish" due to its heavy silt load. Starting in the central Rocky Mountains of Colorado, it flows generally southwest across the Colorado Plateau and through the Grand Canyon before reaching Lake Mead on the Arizona–Nevada border, where it turns south toward the international border. After entering Mexico, the Colorado approaches the mostly dry Colorado River Delta at the tip of the Gulf of California between Baja California and Sonora. Known for its dramatic canyons, whitewater rapids, and eleven U.S. National Parks, the Colorado River and its tributaries are a vital source of water for 40 million people. An extensive system of dams, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canyon
A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosive activity of a river over geologic time scales. Rivers have a natural tendency to cut through underlying surfaces, eventually wearing away rock layers as sediments are removed downstream. A river bed will gradually reach a baseline elevation, which is the same elevation as the body of water into which the river drains. The processes of weathering and erosion will form canyons when the river's headwaters and estuary are at significantly different elevations, particularly through regions where softer rock layers are intermingled with harder layers more resistant to weathering. A canyon may also refer to a rift between two mountain peaks, such as those in ranges including the Rocky Mountains, the Alps, the Himalayas or the Andes. Usually, a river or stream carves out such splits between mountains. Examples of mountain-type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subansiri River
The Subansiri River; is a trans- Himalayan river and a tributary of the Brahmaputra River that flows through Tibet's Lhünzê County, Shannan Prefecture and the Indian states of Arunachal Pradesh and Assam. The Subansiri is long, with a drainage basin . It is the largest tributary of the Brahmaputra contributing 7.92% of the Brahmaputra's total flow. Name and etymology The name is derived from a Sanskrit word ''svarṇa'' (), meaning 'gold'. Originally the name applied to the river only after the confluence of the Chayul Chu and Tsari Chu rivers at Gelensiniak. In early maps of independent India, Tsari Chu was marked as the main Subansiri river. However, over time, the name has been transferred to Chayul Chu. Within Tibet, the rivers are named after the locations they flow from such as Loro Chu, Nye Chu, Char Chu and Chayul Chu, all of which apply to the Subansirir or its tributaries. Course The Subansiri River originates in the Himalayas near Mount Porom in the Tibe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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