As a result, the tributary streams make shape bends and enter the main stream at high angles. Remember that the term dendritic has been taken after the Greek word 'dendron' meaning a tree. They develop where the river channel follows the slope of the terrain. Drainage pattern is the pattern formed by the streams, rivers, and lakes in a particular drainage basin. Geomorphologists and hydrologists often view streams as being part of drainage basins. In an annular drainage pattern streams follow a roughly circular or concentric path along a belt of weak rock, resembling in plan a ringlike pattern.
Consequent Rivers The Rivers which follow the general direction of slope are known as the consequent rivers. Rectangular drainage patternRectangular drainage develops on rocks that are of approximately uniform resistance to erosion, but which have two directions of jointing at approximately right angles. This pattern is also found in the Girnar Hills Kathiwar, Gujarat , and Mikir Hills of Assam. The benefit of this type of subsurface drainage is that it makes the use of machinery difficult. In some cases, particularly where deep fill has been made, it may be necessary to cut and fill again, using tractors and scrapers to eliminate depressions and reverse surface grades. The western coastal plains of India represent several examples of parallel drainage patterns where the streams after taking their sources from the western flanks of the Western Ghats drain in straight courses towards west to empty into the Arabian Sea. The rivers occupying east-west trenches in the Himalayas form herringbone pattern.
Make the first two passes on opposite diagonals as noted in and the last pass in the direction of cultivation. It is most commonly found in a scarp-and-vale terrain where drainage has become adjusted to structure. Dendritic patterns, which are by far the most common, develop in areas where the rock or unconsolidated material beneath the stream has no particular fabric or structure and can be eroded equally easily in all directions. Dendritic drainage patterns are mostly found upon nearly horizontal sedimentary rocks or in areas of massive igneous rocks. A deranged drainage system is a drainage system in drainage basins where there is no coherent pattern to the rivers and lakes. This results from a partial adaptation to an underground circular structure; a dome like igneous intrusion batholith. The tributaries join their master streams almost at right angles and thus a rectangular drainage pattern is formed fig.
Such a pattern develops upon rocks of uniform resistance and demonstrates lack of structural control. Rivers like Narmada, son and Mahanadi originating from Amarkantak Hills flow in different directions and are good Examples of radial pattern. More rapid removal may be necessary for higher value truck crops. Tributaries join the main stream at nearly right angles. These tributary streams are called as lateral consequent streams. Rectangular Drainage The drainage pattern marked by right-angled bends and right-angled junctions between tributaries and the main stream is known as rectangular drainage. The streams emerge from the surrounding uplands.
The effect is a stream system in which streams include mainly of straight line segments with right angle bends and tributaries join larger streams at right angles. The resultant drainage pattern or drainage network is the spatial relationship of all streams within a drainage system. Tributary streams tend to stretch out in a parallel-like fashion following the slope of the surface. On these features the drainage may exhibit a combination of radial patterns A good example of a radial drainage pattern is provided by the rivers originating from the Amarkantak Mountain. The number, size, and shape of the drainage basins found in an area varies and the larger the topographic map, the more information on the drainage basin is available.
This pattern can be found with the in Nepal. A surface drainage system consists of shallow ditches and should include land smoothing or land grading. Russel 1898 , is used to denote the most common type of drainage pattern and is a distinctive feature of the regions having horizontally bedded sedimentary rocks or massive igneous rocks. Rivers like Narmada, Son and Mahanadi originating from Amarkantak Hills flow in different directions and are good examples of radial pattern. The radial drainage pattern resembles the spokes of a wheel. The finished surface should be free from minor depressions so that runoff will flow unobstructed to field or lateral ditches. It happens in areas where there has been much geological disruption.
These are basically the consequent streams as they follow the slope of the land. The tributaries originating from the steep sides of parallel ridges join the longtitudinal master consequent occupying the valley at acute angles fig. This also includes the disappearing drainage pattern, where the streams merge in the desert sands and fail to reach the sea coast. It is essential that lateral ditches be deep enough to drain the field ditches completely enough to permit crossing by farm machinery. But there are some common characteristics, which enable us to distinguish the different drainage patterns.
Radial drainage pattern Radial drainage patterngeological features on which radial drainage commonly develops are domes and laccoliths. The Trellis Drainage Pattern: The tributaries join the main stream at right angles and thus form a trellis. The Subsurface drainage system includes: Deep open drains: The overloaded water from the root zone flows into the open drains. This pattern may be found around maturely dissected domes which have alternating belts of strong and weak rock encircling them. It differs from trellis pattern drainage, since it is more irregular and its tributary streams are not as long or as parallel as in trellis drainage. These results from a partial adaptation to an underground circular structure i.