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Home  ›  List These In Order Of Size: Stream, Rill, Gully, Runoff, River. Why Do Rivers Meander?

List These In Order Of Size: Stream, Rill, Gully, Runoff, River. Why Do Rivers Meander?

Written By Thursday, April 14, 2022 Add Comment Edit

Sinuous bend in a series in the channel of a river

A stream bed post-obit a tilted valley. The maximum gradient is along the downwards-valley axis represented by a hypothetical directly channel. Meanders develop, which lengthen the course of the stream, decreasing the gradient.

Meanders of the Rio Cauto at Guamo Embarcadero, Republic of cuba

A meander is one of a series of regular sinuous curves in the channel of a river or other watercourse. Information technology is produced equally a watercourse erodes the sediments of an outer, concave banking company (cutting bank) and deposits sediments on an inner, convex banking concern which is typically a point bar. The result of this coupled erosion and sedimentation is the formation of a sinuous grade as the aqueduct migrates back and forth beyond the centrality of a floodplain.[1] [2]

The zone within which a meandering stream periodically shifts its aqueduct is known every bit a meander belt. It typically ranges from 15 to 18 times the width of the aqueduct. Over time, meanders migrate downstream, sometimes in such a short time as to create civil engineering challenges for local municipalities attempting to maintain stable roads and bridges.[one] [2]

The caste of meandering of the channel of a river, stream, or other watercourse is measured past its sinuosity. The sinuosity of a watercourse is the ratio of the length of the aqueduct to the straight line down-valley distance. Streams or rivers with a single channel and sinuosities of 1.v or more are defined as meandering streams or rivers.[1] [3]

Origin of term [edit]

The term derives from the winding river Menderes located in Asia-Minor and known to the Ancient Greeks as Μαίανδρος Maiandros (Latin: Maeander),[4] [5] characterised past a very convoluted path along the lower reach. Equally a result, even in Classical Greece (and in subsequently Greek thought) the proper noun of the river had become a common substantive significant annihilation convoluted and winding, such every bit decorative patterns or speech and ideas, equally well equally the geomorphological characteristic.[6] Strabo said: '…its course is so exceedingly winding that everything winding is called meandering.'[7]

The Meander River is south of Izmir, e of the ancient Greek town of Miletus, now Milet, Turkey. It flows through series of three graben in the Menderes Massif, but has a flood patently much wider than the meander zone in its lower reach. Its mod Turkish name is the Büyük Menderes River.[8]

Governing physics [edit]

Straight channel culminating in a single bend

Meanders are a result of the interaction of water flowing through a curved channel with the underlying river bed. This produces helicoidal flow, in which water moves from the outer to the inner bank forth the river bed, and so flows back to the outer banking concern near the surface of the river. This in plow increases carrying capacity for sediments on the outer bank and reduces it on the inner banking concern, so that sediments are eroded from the outer bank and redeposited on the inner banking concern of the next downstream meander.[9]

When a fluid is introduced to an initially straight channel which and so bends, the sidewalls induce a pressure slope that causes the fluid to alter course and follow the bend. From here, two opposing processes occur: (1) irrotational flow and (ii) secondary flow. For a river to meander, secondary catamenia must dominate.

Irrotational period: From Bernoulli's equations, high pressure level results in low velocity. Therefore, in the absence of secondary menses we would await low fluid velocity at the outside bend and high fluid velocity at the inside bend. This archetype fluid mechanics result is irrotational vortex flow. In the context of meandering rivers, its effects are dominated past those of secondary period.

Secondary flow: A force balance exists between pressure forces pointing to the inside bend of the river and centrifugal forces pointing to the outside bend of the river. In the context of meandering rivers, a boundary layer exists within the sparse layer of fluid that interacts with the river bed. Inside that layer and post-obit standard boundary-layer theory, the velocity of the fluid is effectively zero. Centrifugal forcefulness, which depends on velocity, is besides therefore effectively zero. Pressure force, however, remains unaffected by the purlieus layer. Therefore, within the purlieus layer, pressure force dominates and fluid moves forth the bottom of the river from the outside bend to the within bend. This initiates helicoidal menstruum: Along the river bed, fluid roughly follows the curve of the channel but is as well forced toward the within bend; away from the river bed, fluid also roughly follows the curve of the channel just is forced, to some extent, from the within to the outside bend.

The higher velocities at the outside bend lead to higher shear stresses and therefore issue in erosion. Similarly, lower velocities at the inside bend cause lower sheer stresses and deposition occurs. Thus meander bends erode at the exterior bend, causing the river to condign increasingly sinuous (until cutoff events occur). Deposition at the within curve occurs such that for well-nigh natural meandering rivers, the river width remains almost constant, fifty-fifty as the river evolves.[ten]

In a speech before the Prussian Academy of Sciences in 1926, Albert Einstein suggested that considering the Coriolis force of the earth can cause a small imbalance in velocity distribution, such that velocity on one bank is higher than on the other, it could trigger the erosion on one bank and deposition of sediment on the other that produces meanders[11] Notwithstanding, Coriolis forces are probable insignificant compared with other forces acting to produce river meanders.[12]

Meander geometry [edit]

Uvac coulee meander, Serbia

The technical description of a meandering watercourse is termed meander geometry or meander planform geometry.[xiii] Information technology is characterized as an irregular waveform. Platonic waveforms, such as a sine wave, are one line thick, simply in the case of a stream the width must be taken into consideration. The bankfull width is the altitude across the bed at an average cantankerous-department at the full-stream level, typically estimated past the line of lowest vegetation.

Every bit a waveform the meandering stream follows the downward-valley axis, a straight line fitted to the curve such that the sum of all the amplitudes measured from information technology is nil. This axis represents the overall management of the stream.

At any cross-section the flow is following the sinuous axis, the centerline of the bed. 2 consecutive crossing points of sinuous and downwardly-valley axes define a meander loop. The meander is ii consecutive loops pointing in opposite transverse directions. The distance of one meander along the downward-valley axis is the meander length or wavelength. The maximum altitude from the down-valley centrality to the sinuous axis of a loop is the meander width or amplitude. The class at that point is the apex.

In contrast to sine waves, the loops of a meandering stream are more virtually round. The curvature varies from a maximum at the noon to goose egg at a crossing betoken (straight line), also called an inflection, considering the curvature changes management in that vicinity. The radius of the loop is the straight line perpendicular to the down-valley centrality intersecting the sinuous axis at the apex. As the loop is not ideal, boosted data is needed to characterize it. The orientation angle is the angle betwixt sinuous axis and down-valley axis at whatsoever point on the sinuous centrality.

A loop at the apex has an outer or concave bank and an inner or convex banking company. The meander belt is defined past an average meander width measured from outer depository financial institution to outer banking concern instead of from centerline to centerline. If there is a flood plain, information technology extends beyond the meander belt. The meander is and so said to be costless—it can exist plant anywhere in the flood plainly. If at that place is no flood evidently, the meanders are fixed.

Various mathematical formulae relate the variables of the meander geometry. As it turns out some numerical parameters can be established, which appear in the formulae. The waveform depends ultimately on the characteristics of the flow but the parameters are independent of it and plainly are caused past geologic factors. In general the meander length is 10–fourteen times, with an average xi times, the fullbank channel width and iii to 5 times, with an average of iv.7 times, the radius of curvature at the apex. This radius is two–iii times the aqueduct width.[fourteen]

A meander has a depth pattern besides. The cross-overs are marked by riffles, or shallow beds, while at the apices are pools. In a puddle management of flow is down, scouring the bed textile. The major volume, notwithstanding, flows more slowly on the inside of the curve where, due to decreased velocity, it deposits sediment.[15]

The line of maximum depth, or channel, is the thalweg or thalweg line. It is typically designated the borderline when rivers are used equally political borders. The thalweg hugs the outer banks and returns to eye over the riffles. The meander arc length is the distance along the thalweg over one meander. The river length is the length along the centerline.[15]

Formation [edit]

Life history of a meander

In one case a channel begins to follow a sinusoidal path, the amplitude and concavity of the loops increase dramatically. This is due to the effect of helical menstruation which sweeps dense eroded material towards the inside of the curve, and leaves the outside of the curve unprotected and vulnerable to accelerated erosion. This establishes a positive feedback loop. In the words of Elizabeth A. Wood:[sixteen]

'…this process of making meanders seems to be a self-intensifying process…in which greater curvature results in more erosion of the bank, which results in greater curvature…'

The cross-current along the flooring of the aqueduct is role of the secondary flow and sweeps dense eroded material towards the inside of the bend.[17] The cross-current then rises to the surface near the inside and flows towards the outside, forming the helical catamenia. The greater the curvature of the curve, and the faster the flow, the stronger is the cantankerous-current and the sweeping.[eighteen]

Due to the conservation of angular momentum the speed on the inside of the bend is faster than on the exterior.[19]

Since the flow velocity is diminished, so is the centrifugal pressure. The pressure of the super-elevated column prevails, developing an unbalanced gradient that moves water back across the lesser from the exterior to the inside. The flow is supplied by a counter-flow across the surface from the inside to the outside.[20] This entire situation is very similar to the Tea leaf paradox.[21] This secondary flow carries sediment from the outside of the bend to the inside making the river more meandering.[22]

Equally to why streams of any size become sinuous in the showtime place, there are a number of theories, non necessarily mutually exclusive.

Stochastic theory [edit]

The stochastic theory tin can take many forms but one of the most general statements is that of Scheidegger: 'The meander railroad train is assumed to be the upshot of the stochastic fluctuations of the direction of period due to the random presence of direction-changing obstacles in the river path.'[23] Given a flat, smoothen, tilted artificial surface, rainfall runs off it in sheets, merely even in that instance adhesion of water to the surface and cohesion of drops produce rivulets at random. Natural surfaces are rough and erodible to dissimilar degrees. The result of all the concrete factors acting at random is channels that are not directly, which and then progressively get sinuous. Even channels that appear straight have a sinuous thalweg that leads somewhen to a sinuous aqueduct.

Equilibrium theory [edit]

In the equilibrium theory, meanders subtract the stream gradient until an equilibrium betwixt the erodibility of the terrain and the transport capacity of the stream is reached.[24] A mass of water descending must give up potential free energy, which, given the aforementioned velocity at the stop of the drop as at the first, is removed past interaction with the textile of the stream bed. The shortest altitude; that is, a straight aqueduct, results in the highest energy per unit of length, disrupting the banks more, creating more sediment and aggrading the stream. The presence of meanders allows the stream to adjust the length to an equilibrium energy per unit of measurement length in which the stream carries away all the sediment that information technology produces.

Geomorphic and morphotectonic theory [edit]

Geomorphic refers to the surface construction of the terrain. Morphotectonic ways having to do with the deeper, or tectonic (plate) structure of the rock. The features included nether these categories are not random and guide streams into non-random paths. They are predictable obstacles that instigate meander formation past deflecting the stream. For instance, the stream might be guided into a error line (morphotectonic).[25]

Associated landforms [edit]

Cut banking concern [edit]

A cut bank is an often vertical bank or cliff that forms where the exterior, concave bank of a meander cuts into the floodplain or valley wall of a river or stream. A cutbank is also known either as a river-cut cliff, river cliff, or a bluff and spelled as cutbank.[1] Erosion that forms a cut bank occurs at the exterior bank of a meander because helicoidal flow of water keeps the bank washed make clean of loose sand, silt, and sediment and subjects information technology to constant erosion. As a event, the meander erodes and migrates in the direction of the outside bend, forming the cut bank.[26] [27]

Equally the cutting bank is undermined past erosion, information technology commonly collapses as slumps into the river channel. The slumped sediment, having been broken up by slumping, is readily eroded and carried toward the middle of the channel. The sediment eroded from a cut bank tends to be deposited on the point bar of the next downstream meander, and not on the point bar opposite it.[28] [26] This can be seen in areas where copse grow on the banks of rivers; on the within of meanders, trees, such as willows, are often far from the banking company, whilst on the outside of the bend, the tree roots are oft exposed and undercut, somewhen leading the trees to fall into the river.[28] [29]

Meander cutoff [edit]

The Rincon on Lake Powell in southern Utah. It is an incised cutoff (abandoned) meander.

A meander cutoff, likewise known as either a cutoff meander or abandoned meander, is a meander that has been abandoned past its stream after the formation of a neck cutoff. A lake that occupies a cutoff meander is known every bit an oxbow lake. Cutoff meanders that have cut downward into the underlying bedrock are known in full general as incised cutoff meanders.[ane] Equally in the case of the Anderson Bottom Rincon, incised meanders that have either steep-sided, frequently vertical walls, are often, but non e'er, known equally rincons in the southwest United States.[30] Rincon in English is a nontechnical give-and-take in the southwest U.s.a. for either a small-scale secluded valley, an alcove or athwart recess in a cliff, or a bend in a river.[31]

Incised meanders [edit]

The meanders of a stream or river that has cutting its bed downwards into the bedrock are known as either incised, intrenched, entrenched, inclosed or ingrown meanders. Some Earth scientists recognize and use a effectively subdivision of incised meanders. Thornbury[32] argues that incised or inclosed meanders are synonyms that are appropriate to describe any meander incised downward into bedrock and defines enclosed or entrenched meanders as a subtype of incised meanders (inclosed meanders) characterized by a symmetrical valley sides. He argues that the symmetrical valley sides are the direct upshot of rapid down-cutting of a watercourse into boulder.[1] [33] In improver, as proposed by Rich,[34] Thornbury argues that incised valleys with a pronounced asymmetry of cross section, which he called ingrown meanders, are the result of the lateral migration and incision of a meander during a period of slower channel downcutting. Regardless, the formation of both entrenched meanders and ingrown meanders is idea to require that base level falls as a outcome of either relative change in mean sea level, isostatic or tectonic uplift, the breach of an ice or landslide dam, or regional tilting. Classic examples of incised meanders are associated with rivers in the Colorado Plateau, the Kentucky River Palisades in central Kentucky, and streams in the Ozark Plateau.[33] [35]

As noted above, information technology was initially either argued or presumed that an incised meander is characteristic of an antecedent stream or river that had incised its aqueduct into underlying strata. An antecedent stream or river is one that maintains its original class and design during incision despite the changes in underlying rock topography and stone types.[32] [33] However, afterwards geologists[36] argue that the shape of an incised meander is not always, if e'er, "inherited," due east.one thousand., strictly from an antecedent meandering stream where it meander pattern could freely develop on a level floodplain. Instead, they argue that equally fluvial incision of bedrock proceeds, the stream form is significantly modified past variations in stone type and fractures, faults, and other geological structures into either lithologically conditioned meanders or structurally controlled meanders.[33] [35]

Oxbow lakes [edit]

The oxbow lake, which is the near common type of fluvial lake, is a crescent-shaped lake that derives its proper noun from its distinctive curved shape.[37] Oxbow lakes are also known as cutoff lakes.[1] Such lakes class regularly in undisturbed floodplains as a result of the normal process of fluvial meandering. Either a river or stream forms a sinuous channel as the outer side of its bends are eroded away and sediments accrue on the inner side, which forms a meandering horseshoe-shaped curve. Somewhen as the result of its meandering, the fluvial aqueduct cuts through the narrow neck of the meander and forms a cutoff meander. The terminal intermission-through of the cervix, which is called a neck cutoff, often occurs during a major flood because that is when the watercourse is out of its banks and can flow directly beyond the neck and erode it with the total strength of the flood.[28] [38]

After a cutoff meander is formed, river water flows into its cease from the river builds pocket-sized delta-like feature into either end of it during floods. These delta-like features block either end of the cutoff meander to grade a stagnant oxbow lake that is separated from the flow of the fluvial channel and independent of the river. During floods, the flood waters deposit fine-grained sediment into the oxbow lake. As a issue, oxbow lakes tend to become filled in with fine-grained, organic-rich sediments over time.[28] [38]

Point bar [edit]

A point bar, which is also known as a meander bar, is a fluvial bar that is formed by the slow, often episodic, addition of private accretions of noncohesive sediment on the inside banking company of a meander by the accompanying migration of the channel toward its outer bank.[1] [26] This process is called lateral accession. Lateral accretion occurs mostly during loftier h2o or floods when the bespeak bar is submerged. Typically, the sediment consists of either sand, gravel, or a combination of both. The sediment comprising some point bars might grade downstream into silty sediments. Because of the decreasing velocity and strength of current from the thalweg of the aqueduct to the upper surface of point bar when the sediment is deposited the vertical sequence of sediments comprising a indicate bar becomes finer upward within an individual point bar. For example, it is typical for indicate confined to fine upward from gravel at the base to fine sands at the top. The source of the sediment is typically upstream cut banks from which sand, rocks and debris has been eroded, swept, and rolled across the bed of the river and downstream to the inside bank of a river bend. On the inside bend, this sediment and debris is somewhen deposited on the slip-off gradient of a indicate bar.[1] [26] [27]

Scroll-bars [edit]

Gyre-bars are a result of continuous lateral migration of a meander loop that creates an asymmetrical ridge and swale topography[39] on the inside of the bends. The topography is mostly parallel to the meander, and is related to migrating bar forms and back bar chutes,[40] which cleave sediment from the outside of the bend and deposit sediment in the slower flowing water on the inside of the loop, in a procedure called lateral accretion. Scroll-bar sediments are characterized by cross-bedding and a pattern of fining upwardly.[41] These characteristics are a issue of the dynamic river system, where larger grains are transported during high energy flood events and so gradually dice down, depositing smaller material with time (Batty 2006). Deposits for meandering rivers are generally homogeneous and laterally extensive unlike the more heterogeneous braided river deposits.[42] There are two distinct patterns of gyre-bar depositions; the eddy accession scroll bar design and the point-bar scroll pattern. When looking down the river valley they tin exist distinguished considering the point-bar scroll patterns are convex and the eddy accretion scroll bar patterns are concave.[43]

Scroll bars ofttimes look lighter at the tops of the ridges and darker in the swales. This is because the tops tin can be shaped by wind, either adding fine grains or by keeping the area unvegetated, while the darkness in the swales tin can be attributed to silts and clays washing in during loftier water periods. This added sediment in improver to water that catches in the swales is in turn is a favorable surroundings for vegetation that will also accumulate in the swales.

Slip-off slope [edit]

Depending upon whether a meander is function of an entrenched river or part of a freely meandering river within a floodplain, the term slip-off slope can refer to two different fluvial landforms that comprise the inner, convex, banking company of a meander loop. In instance of a freely meandering river on a floodplain, a sideslip-off slope is the within, gently sloping bank of a meander on which sediments episodically accrue to form a point bar as a river meanders. This type of sideslip-off slope is located opposite the cutbank.[44] This term tin can also be practical to the inside, sloping banking concern of a meandering tidal channel.[45]

In case of an entrenched river, a slip-off slope is a gently sloping bedrock surface that rises from the inside, concave bank of an asymmetrically entrenched river. This type of slip-off gradient is oft covered by a thin, discontinuous layer of alluvium. It is produced by the gradual outward migration of the meander as a river cuts downwards into bedrock.[46] [47] A terrace on the sideslip-off slope of a meander spur, known as sideslip-off gradient terrace, can formed by a cursory halt during the irregular incision past an actively meandering river.[48]

Derived quantities [edit]

The meander ratio[49] or sinuosity alphabetize[50] is a means of quantifying how much a river or stream meanders (how much its course deviates from the shortest possible path). It is calculated as the length of the stream divided by the length of the valley. A perfectly straight river would accept a meander ratio of 1 (it would exist the aforementioned length as its valley), while the higher this ratio is in a higher place 1, the more the river meanders.

Sinuosity indices are calculated from the map or from an aerial photo measured over a altitude called the reach, which should be at to the lowest degree 20 times the average fullbank channel width. The length of the stream is measured by aqueduct, or thalweg, length over the reach, while the bottom value of the ratio is the downvalley length or air distance of the stream between ii points on it defining the reach.

The sinuosity alphabetize plays a part in mathematical descriptions of streams. The alphabetize may require elaboration, because the valley may meander every bit well—i.e., the downvalley length is not identical to the attain. In that case the valley index is the meander ratio of the valley while the channel index is the meander ratio of the channel. The aqueduct sinuosity index is the aqueduct length divided past the valley length and the standard sinuosity index is the channel index divided by the valley index. Distinctions may become even more subtle.[51]

Sinuosity Index has a non-mathematical utility also. Streams can exist placed in categories arranged by it; for example, when the index is betwixt one and i.5 the river is sinuous, simply if between 1.five and 4, then meandering. The index is a measure besides of stream velocity and sediment load, those quantities being maximized at an alphabetize of one (straight).

Come across likewise [edit]

  • Baer's constabulary
  • Billabong
  • Crevasse splay
  • Helicoidal flow
  • Jet stream
  • Meander cutoffs in Avulsion (river)
  • Meander scar
  • Riffle-pool sequence

References and notes [edit]

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  2. ^ a b Charlton, R., 2007. Fundamentals of fluvial geomorphology. Routledge, New York, New York. 234 pp. ISBN 0-415-33453-5
  3. ^ Leopold, L.B., Wolman, Chiliad.One thousand., Wolman, M.G. and Wolman, Chiliad.G., 1957. River Channel Patterns: Braided, Meandering, and Straight. United States Geological Survey Professional Newspaper no. 282B, US Authorities Printing Part, Washington DC., 47 pp.
  4. ^ "Meander". Merriam-Webster. Retrieved July 12, 2012.
  5. ^ Leong, Goh Cheng (1995-10-27). Certificate Physics And Homo Geography; Indian Edition. Oxford Academy Press. pp. 41–42. ISBN978-0-nineteen-562816-6.
  6. ^ "Meander". Online Etymology Dictionary. Retrieved July 12, 2012.
  7. ^ Strabo, Geography, Volume 12 Chapter eight Section 15.
  8. ^ Gürbüz, Alper; Kazancı, Nizamettin (2019). "The Büyük Menderes River: Origin of Meandering Phenomenon". Landscapes and Landforms of Turkey. World Geomorphological Landscapes: 509–519. doi:10.1007/978-3-030-03515-0_29. ISBN978-3-030-03513-vi. S2CID 134826361.
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  10. ^ Weiss, Samantha Freeman. (April 2016). Meandering River Dynamics (Doctoral dissertation). Retrieved from Ideals. https://www.ideals.illinois.edu/bitstream/handle/2142/92706/WEISS-DISSERTATION-2016.pdf?sequence=1&isAllowed=y
  11. ^ "Albert Einstein, river meandering, Hans Einstein, sediment transport, Victor Miguel Ponce". Archived from the original on 2017-11-xix.
  12. ^ Martínez, Alberto A. (March 2014). "The questionable inventions of the clever Dr. Einstein: József Illy: The practical Einstein: Experiments, patents, inventions. Baltimore: Johns Hopkins University Press, 2012, 14+202pp, $lx.00 HB". Metascience. 23 (1): 49–55. doi:x.1007/s11016-013-9819-x. S2CID 169290222.
  13. ^ The technical definitions of this section rely heavily on Julien, Pierre Y. (2002). River Mechanics . Cambridge University press. pp. 179–184. ISBN0-521-52970-0. In add-on concepts are utilized from Graf, Walter (1984). Hydraulics of Sediment Transport. Water Resources Publications. pp. 261–265. ISBN0-918334-56-X.
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  17. ^ Hickin 2003, p. 432. "Ane of the of import consequences of helical flow in meanders is that sediment eroded from the outside of a meander bend tends to move to the inner bank or point bar of the next downstream curve."
  18. ^ Hickin 2003, p. 434.
  19. ^ Hickin 2003, p. 432. "In the absenteeism of secondary flow, bend menstruation seeks to conserve angular momentum and then that information technology tends to accommodate to that of a gratis vortex with high velocity at the smaller radius of the inner banking company and lower velocity at the outer bank where radial acceleration is lower."
  20. ^ Hickin 2003, p. 432. "Near the bed, where velocity and thus the centrifugal effects are lowest, the balance of forces is dominated by the inward hydraulic gradient of the super-elevated water surface and secondary period moves toward the inner bank."
  21. ^ Bowker, Kent A. (1988). "Albert Einstein and Meandering Rivers". Globe Scientific discipline History. i (1). Retrieved 2016-07-01 .
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  23. ^ Scheidegger, Adrien Due east. (2004). Morphotectonics. Berlin, New York: Springer. p. 113. ISBNiii-540-20017-7.
  24. ^ Riley, Ann L. (1998). Restoring Streams in Cities: A Guide for Planners, Policymakers and Citizens. Washington DC: Island Press. p. 137. ISBNane-55963-042-half-dozen.
  25. ^ D'Alessandro, Leandro; Miccadei, Enrico; Piacentini, Tommaso (Nov 2008). "Morphotectonic study of the lower Sangro River valley (Abruzzi, Cardinal Italian republic)". Geomorphology. 102 (i): 145–158. Bibcode:2008Geomo.102..145D. doi:10.1016/j.geomorph.2007.06.019.
  26. ^ a b c d Reineck, H.E. and Singh, I.B., 2012. Depositional sedimentary environments: with reference to terrigenous clastics. Springer Science & Business concern Media, New York, New York. 551 pp. ISBN 9783642962912
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  29. ^ Fisk, H.N., 1948. Fine-grained Alluvial Deposits and Their Effects on Mississippi River Activity. State of war Department, Corps of Engineers, Mississippi River Commission, Vicksburg, Mississippi. 2 Vols., 82 pp.
  30. ^ Shoemaker, E.K. and Stephens, H.Grand., 1975. First photographs of the Coulee Lands. in Fassett, J.Due east., ed., pp. 111–122, Canyonlands Land, A Guidebook of the 4 Corners Geological Order 8th Field Briefing — September 22–25, 1975. Four Corners Geological Society, Durango, Colorado. pp. 278.
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  34. ^ Rich, J.L., 1914. Sure types of stream valleys and their meaning. The Journal of Geology, 22(v), pp. 469–497.
  35. ^ a b Barbour, J.R., 2008. The origin and significance of sinuosity along incising boulder rivers. Doctoral dissertation, Columbia University, New York, New York, 172 pp.
  36. ^ Hack, J.T., and Young, R.S., 1959. Intrenched meanders of the North Fork of the Shenandoah River, Virginia. Usa Geological Survey Professional Paper 354-A, 10 pp.
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Bibliography [edit]

  • Hickin, Edward J. (2003). "Meandering Channels". In Middleton, Gerard 5. (ed.). Encyclopedia of Sediments and Sedimentary Rocks. Kluwer Academic Encyclopedia of Earth Sciences. Dordrecht; Boston: Kluwer Academic Publishers. pp. 430–434. ISBNane-4020-0872-iv.
  • Leopold, Luna B.; Langbein, West.B. (June 1966). "River Meanders". Scientific American. 214 (half dozen): threescore. Bibcode:1966SciAm.214f..60L. doi:10.1038/scientificamerican0666-60. Virtual Luna Leopold
  • Thonemann, P., The Maeander Valley: A historical geography from Antiquity to Byzantium (Cambridge, 2011) (Greek Culture in the Roman Globe Series).

External links [edit]

  • Movshovitz-Hadar, Nitsa; Alla Shmuklar (2006-01-01). "River Meandering and a Mathematical Model of this Phenomenon". Physicalplus. Israel Physical Gild (IPS) (vii).

List These In Order Of Size: Stream, Rill, Gully, Runoff, River. Why Do Rivers Meander?,

Source: https://en.wikipedia.org/wiki/Meander

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