河道遷移或河流改道(英語:river channel migration)是指沖積河道在氾濫平原橫向遷移的現象。這個過程主要是由河岸侵蝕和岸壩沉積共同造成的。一般在曲流河。或辮狀河中常見[1]。
當水流進入沖積河流的彎道時,因離心力引起了螺旋流(英語:helicoidal flow),螺旋流在一邊的河岸侵蝕堤岸,被侵蝕的沉積物在對面河岸沉積,造成岸壩[2][3].
Bierman, Paul R., and David R. Montgomery. Key Concepts in Geomorphology. New York: W.H. Freeman, 2014. Print
Hickin, E. J. (1974). "The development of meanders in natural river-channels". American Journal of Science. 274 (4): 414–442. Bibcode:1974AmJS..274..414H. doi:10.2475/ajs.274.4.414
Howard, Alan D. "Modeling channel migration and floodplain sedimentation in meandering streams." Lowland floodplain rivers: geomorphological perspectives(1992): 1-41