THE TRANSGRESSIVE AND REGRESSIVE MOVEMENTS OF THE ISLANDS AND ISLAND CLUSTERS IN THE BRAIDED RIVERBEDS AT THE WIDE FLOOD-PLAINS
https://doi.org/10.15356/0435-4281-2015-2-16-27
Abstract
The mechanism of the islands and island clusters movements is suggested. The velocity field and circulating flows usually lead to washing of their upper part and to formation of spits in their tails which result in the island's displacement. If the sediment run-off exceeds carrying capacity of the river, then backwater due to the island existence causes accumulation at the upper part of the island and its regressive displacement. Symmetrically braided river bed expresses directional development of the bed deformation (the sediment accumulation and the bottom level rising). Regressive displacement often is manifested in the formation of midstream sandbank upstream the island due to water surface inclination. The backwater appears at some distance from the head of the island and the flow is directed to the one or another braid during different phases of a regime. These flows are carrying sediments out from under the ridge, determine the midstream sandbank stabilization, and prevent its coming onto the island. Localities of the island's regressive movement were determined: in the periphery of the bed, in the zones of backwater upstream the confluence, before the valley bottom narrowing, downstream the local sources of sediments influx. Conditions of island stabilization depend on the meanders formation in the braids circumflexing the island, geomorphologic limitations (transition from the wide flood-plain to incised river-bed, constraints by bedrock coast promontories), and transition from the braided bed to the wandering or relatively rectilinear not braided one. The meander bars and midstream sandbanks consecutive coming on to the point of braiding from the upstream reach is also significant.
About the Authors
R. S. ChalovRussian Federation
Geographical Department
O. M. Kirik
Russian Federation
Geographical Department
References
1. Makkaveyev N.I. Ruslo reki I eroziya v ee basseyne (River channel and erosion in its basin). Moscow: IG RAS, 1955, 347 p.
2. Popov I.V. Deformatsiya rechnykh rusel I gidrotekhnicheskoe stroitelstvo (River channel deformations and hydraulic engineering construction). Leningrad: Gydrometeoizdat, 1955, 328 p.
3. Chalov R.S. Morphological types of braided channels of plain rivers. Water resources, 1998, vol. 25, no. 2, pp. 179-185 (in Russ.).
4. Chalov R.S. Complex braided patterns of plain rivers: origin, morphology and planform dynamics. Water resources, 2001, vol. 23, no. 2, pp. 166-171 (in Russ.).
5. Chalov R.S., Chalov S.R., Alekseevskiy N.I. Structural levels of and typification of braided channels. Vestn. Mos. Univ., Ser. 5, Geogr, 2011, no. 4, pp. 8-15 (in Russ.)
6. Rosgen D.L. A classification of natural rivers. Catena, 1994, 22, pp. 169-199.
7. Chalov R.S. Riverbed science: theory, geography, practice. Chapter 2. Morfodinamika rechnykh rusel (Morphodynamics of river channels). Moscow: KRASAND, 2011, 960 p.
8. Vodnye puti basseyna Leny (Waterway of the Lena river basin). Moscow: MIKIS, 1995, 600 p.
9. Chalov R.S. Basic circuitry of braided channels regulation on navigable rivers, in Sovremennoe sostoyanie vodnykh putey I problemy ruslovykh protsessov (State-of-the-art of waterways and issues of channel processes science). Moscow: MGU (Publ.), 1999, pp. 26-31.
10. Ruslovye protsessy I vodnye puti na rekah Obskogo basseyna (Channel processes and navigable waterway of the Ob’ river basin). Novosibirsk: RIPELplus (Publ.), 2001, 300 p.
11. Ruslovye protsessy I vodnye puti na rekah basseyna Severnoy Dviny (Channel processes and navigable waterway of the Severnaya Dvina river basin). Moscow: Journal RT, 2012, 492 p.
12. Tarbeeva A.M. Islands forming and evolution in the Ob’ river channel, in Erosionnye, ruslovye protsessy I problemy ih gidroekologii (Erosion and channel processes and hydroecological problems). Moscow: MGU (Publ.), 2004, pp. 195-201.
13. Makkaveev N.I. Regressive reorganization of river islands. Meteor. I hydrol., 1948, no. 4, pp. 44-50 (in Russ.).
14. Makkaveev N.I., Chalov R.S. Morphological indications of actual accumulation processes in the river valley. Izv. Acad. Nauk SSSR, Ser. Geogr., 1963, no. 3, pp. 84-89 (in Russ.).
15. Proektirovanie sudovykh hodov na svobodnykh rekah (Development of navigation waterways in unconfined rivers). CNIIEVT, iss. 36, 1964, 262 p.
16. Chalov R.S. Geograficheskie issledovaniya ruslovykh processov (Geographical research of channel processes). Moscow: MGU (Publ.), 1979, 232 p.
17. Makkaveyev N.I. Teoreticheskie I prikladnye voprosy pochvovedeniya I ruslovykh processov (Theoretical and applied questions of soil and channel processes sciences). Moscow: MGU (Publ.), 2003, 272 p.
18. Chalov R.S. Morphological manifestations of actual vertical channel deformations in river valleys. Geomorfologiya (Geomorphology RAS), 2007, no. 2, pp. 28-36 (in Russ.).
19. Chalov R.S. Riverbed science: theory, geography, practice. Chapter 1. Ruslovye protsessy: factory, mekhanizmy, formy proyavleniya I usloviya formirovaniya rechnykh rusel (Channel processes, factors, mechanisms, forms of manifestation and forming conditions). Moscow: LKI Publ., 2008, 608 p.
20. Andreev O.V. proektirovanie mostovykh perekhodov (Bridges projection). Moscow: Transport (Publ.), 1980, 215 p.
21. Andreev O.V., Yaroslavtsev I.A. Voprosy ucheta ruslovogo protsessa pri proektirovanii mostovykh perekhodov (Issues of channel processes accounting in projection of highway stream crossings). Moscow: Transjeldorizdat (Publ.), 1953, 40 p.
22. Chalov R.S., Zavadskiy A.S., Panin A.V. Rechnye izluchiny (River bends). Moscow: MGU (Publ.), 2004, 371 p.
23. Klaven A.B., Vinogradov V.A., Kostyuchenko A.A. Nonequilibrium processes in river channels formation, in Makkaveyev’s Readings – 2004. Moscow: MGU (Publ.), 2005, pp. 8-25.
24. Chalov R.S., Kirik O.M., Ilyasov A.K., Botavin D.V. Yakutsk water junction on the Lena river – channel processes issues: history, state-of-the-art, perspectives, management facilities. Vodn. Hoz. Ros., 2012, no. 3, pp. 44-56 (in Russ.).
25. Chalov R.S., Kirik O.M., Ilyasov A.K., Botavin D.V. Long-term directed and periodical changes of the Belogorskie riffles on the Lena river, their transformation and training approaches. Rechn. Transp. (XXI vek), 2014, no. 2, pp. 82-87 (in Russ.).
Review
For citations:
Chalov R.S., Kirik O.M. THE TRANSGRESSIVE AND REGRESSIVE MOVEMENTS OF THE ISLANDS AND ISLAND CLUSTERS IN THE BRAIDED RIVERBEDS AT THE WIDE FLOOD-PLAINS. Geomorfologiya. 2015;(2):16-27. https://doi.org/10.15356/0435-4281-2015-2-16-27
Email this article 