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26-708: The Tagoloan River is the 13th largest river system in the Philippines in terms of watershed size, as classified by the National Water Resources Board . It has an estimated drainage area of 1,704 square kilometres (658 sq mi) covering the provinces of Bukidnon and Misamis Oriental . It has a length of 106 kilometres (66 mi) from its source in Malaybalay City in Bukidnon province. This article related to

52-446: A basin they form centripetal or inland drainage pattern. A deranged drainage system is a drainage system in drainage basins where there is no coherent pattern to the rivers and lakes. These can form in areas with extensive limestone deposits, where surface streams can disappear into the groundwater via caves and subterranean drainage routes. They can also form in areas where there has been much geological disruption. A classic example

78-627: A central playa . An axial river existed in the Espanola Basin as early as 13 million years ago, reaching the Santo Domingo Basin by 6.9 million years ago. However, at this time, the river drained into a playa in the southern Albuquerque Basin where it deposited the Popotosa Formation . The upper reach of this river corresponded to the modern Rio Chama , but by 5 million years ago, an ancestral Rio Grande draining

104-515: A central high point. Volcanos usually have archetypal features on which this commonly develops are modest or hard domes pattern develops when streams flow in many general directions (meaning quite long-term) In India, the Amarkantak range and Ramgarh crater are most archetypal; and Dogu'a Tembien in Ethiopia . When the streams converge at a point, which is generally a depression or

130-406: A drainage system develops on a surface composed of 'younger' rocks, but due to denudation activities this surface of younger rocks is removed and the river continues to flow over a seemingly new surface, but one in fact made up of rocks of old geological formation. Dendritic drainage systems (from Greek δενδρίτης , dendrites , "of or like a tree") are not straight and are the most common form of

156-632: A river in the Philippines is a stub . You can help Misplaced Pages by expanding it . This article about a location in Northern Mindanao region is a stub . You can help Misplaced Pages by expanding it . River system 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. A drainage system

182-591: A single lower base level. An example of an integrated drainage is the area drained by the Rio Grande River . The sedimentary basins forming the modern Rio Grande Valley were not integrated into a single river system draining into the Gulf of Mexico until relatively recent geologic time. Instead, the basins formed by the opening of the Rio Grande rift were initially bolsons , with no external drainage and

208-834: A tangential or greater concentric path along a belt of weak rock so, with others, a roughly traced out ring can be seen. It is best displayed by streams draining a maturely dissected structural dome or basin where erosion has exposed rimming sedimentary strata of greatly varying degrees of hardness, as in the Red Valley , which nearly encircles the domal structure of the Black Hills of South Dakota . Astroblemes and mud diapirs are also thought to be able to cause this kind of drainage pattern. Angular drainage patterns form where bedrock joints and faults intersect at angles other than rectangular drainage patterns. Angles can be more or less than 90 degrees. An integrated drainage

234-730: Is a trans-boundary river that is part of the Koshi or Sapta Koshi river system in Nepal . It originates in the Tibet Autonomous Region of the People's Republic of China where it is called the Phung Chu or Bum-chu . In Tibet, the river is called Bum-chu , also transliterated Phung-Chu or from Chinese as Peng Qu or Pumqu . The Men Qu or Moinqu is an upper tributary draining glaciers from Shishapangma . In Nepal ,

260-429: Is a mature drainage system characteristic of arid climates. It is formed by coalescing of individual basins formerly separated by high ground, such as mountains or ridges. Headward erosion from a lower basin may breach the barrier, as may spilling over from a higher basin due to aggradation (accumulation of sediments in the basin). The effect of integration of a drainage system is to replace local higher base levels with

286-667: Is caused by the location of more than 80 percent of the Arun's drainage area in the rain shadow of the Himalayas . Average annual rainfall in Tibet is about 300 millimetres (12 in). The river leaves the Tibet region at a height of about 3,500 metres (11,500 ft) and crosses the main Himalayan ranges. Leaving their rain shadow, the river's flow increases substantially in the monsoonal climate of east Nepal. The landscape south of

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312-542: Is described as accordant if its pattern correlates to the structure and relief of the landscape over which it flows. A discordant system or pattern does not correlate to the topography and geology of the area. Discordant drainage patterns are classified into two main types: antecedent and superimposed , while ante position drainage patterns combine the two. In antecedent drainage, a river's vertical incision ability matches that of land uplift due to tectonic forces. Superimposed drainage develops differently: initially,

338-836: Is known as Sapta Koshi because of the seven rivers which join in east-central Nepal to form this river. The main rivers forming the Koshi system are – the Sun Koshi , the Indravati River , the Bhoté Koshi , the Dudh Koshi , the Arun River, Barun River , and Tamur River . The combined river flows through the Chatra Gorge in a southerly direction to emerge from the hills. The Sun Koshi contributes 44 per cent of

364-498: Is the Canadian Shield . During the last ice age , the topsoil was scraped off, leaving mostly bare rock. The melting of the glaciers left land with many irregularities of elevation and a great deal of water to collect in the low points, resulting in the region's many lakes. The drainage basins are young and are still sorting themselves out; eventually the system will stabilize. In an annular drainage pattern, streams trace

390-694: The Bum-chu and the lateral valleys formed by its tributaries, the foremost of which are Lolo-chu, Shel-chu, Rongpu-chu, Trakar-chu, Kharda-chu , Ra-chu Tsangpo, and Langkor Gya-chu. The Yeru Tsanpo converges with Bum-chu in Tingkye County , which accommodates the lower Bum-chu valley. Another river that meets Bum-chu is Trakar-chu. The river flows past the town of Kharda , gateway to the Khangzhung east face of Mount Everest . The force of its accumulated waters carves its way, south of Drengtrang, through

416-524: The San Luis basin until a spillover event 440,000 years ago that drained Lake Alamosa and fully reintegrated the San Luis basin into the Rio Grande basin. Integrated drainages were widespread in western North America in the Paleocene and Eocene , and there is evidence of integrated drainages on the surface of Mars . Arun River, China%E2%80%93Nepal The Arun River ( Nepali : अरुण नदी )

442-585: The basin alone. The northern third of the Nepalese portion of the Arun basin supports a rich, though human-modified, forest of mixed hardwoods , Chir pine , fir , and rhododendron at elevations of over 1,000 metres (3,300 ft). The vegetation in the southern two-thirds of the area has been extensively modified for subsistence agriculture. Most of the half million people in the Arun basin live in this southern area between 300 metres (980 ft) and 1,000 metres (3,300 ft) in widely scattered villages near

468-410: The border tends to be steep with less than 15 percent of the area having a sustained slope of less than 15° and is strongly dissected by stream channels. Many of the hill slopes are structurally unstable, and the region is seismically active. The August 1988 Nepal earthquake , with an epicentre around 50 km south of the Arun basin, had a moment magnitude of 6.9 and resulted in more than 100 deaths in

494-511: The bulk rock so erosion tends to preferentially open the joints and streams eventually develop along the joints. The result is a stream system in which streams consist mainly of straight line segments with right-angle bends and tributaries join larger streams at right angles. This pattern can be found with the Arun River in Nepal. In a radial drainage system, the streams radiate outwards from

520-754: The drainage system. In this, there are many sub-tributaries (analogous to the twigs of a tree), which merge into tributaries of the main river (the branches and the trunk of the tree, respectively). They are seen to feed a river channel that matches and is strongly accordant to the overriding gradient of the land. Truly dendritic systems form in V-shaped valleys ; as a result, the rock types must be impervious and non-porous . A parallel drainage system occurs on elongate landforms like outcropping resistant rock bands), typically following natural faults or erosion (such as prevailing wind scars). The watercourses run swift and straight, with very few tributaries, and all flow in

546-637: The eastern San Juan Mountains had joined the ancestral Rio Chama. The ancestral Rio Grande progressively integrated basins to the south, reaching the Palomas basin by 4.5 million years ago, the Mesilla basin by 3.1 million years, to Texas by 2.06 million years, and finally joining the Pecos River at 800,000 years to drain into the Gulf of Mexico. Volcanism in the Taos Plateau reduced drainage from

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572-413: The main chain of the Himalayas directly between the mountain massifs of Makalu and Kangchenjunga into Nepal. Since the river's elevation is about 3,500 metres (11,500 ft) at the border, while Makalu and Kangchenjunga are both about 8,500 metres (27,900 ft), the valley is some 5,000 metres (16,000 ft) deep, one of the world's deepest. The Koshi or Sapta Koshi drains eastern Nepal. It

598-581: The river's name changes to Arun . The Tibetan name Bum-chu may refer to a religious ceremony attempting to divine prospects for the coming year from the level of water in a pot or well, chu is the Tibetan word for water. The river originates near Gutso in Nyalam County of Tibet. Around 17 kilometres (11 mi) downstream, the Men-chu joins it. The Tingri county occupies the upper reaches of

624-539: The same direction. This system forms on very long, uniform slopes, for instance, high rivers flowing southeast from the Aberdare Mountains in Kenya and many rivers of Myanmar . This sometimes indicates a major fault that cuts across an area of steeply folded bedrock. The geometry of a trellis drainage system is similar to that of a common garden trellis . Along a strike valley, smaller tributaries feed into

650-802: The steep slopes of mountainsides. These tributaries enter the main river about perpendicular, causing a trellis-like appearance of the system. They form where hard and soft formations exist on both banks of the main river, and are reflective of height, accentuated by erosion. Trellis drainage is characteristic of folded mountains, such as the Appalachian Mountains in North America and in the north part of Trinidad . Rectangular drainage develops on rocks that are of approximately uniform resistance to erosion , but which have two directions of jointing at approximately right angles or 90 degrees. The joints are usually less resistant to erosion than

676-522: The total water in the Sapta Koshi, the Arun 37 per cent and the Tamur 19 per cent. The Arun is the largest trans-Himalayan river passing through Nepal and also has the greatest snow and ice-covered area of any Nepalese river basin. The Arun drains more than half of the area contributing to the Sapta Koshi river system but provides only about a quarter of the total discharge. This apparent contradiction

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