期刊
GEOMORPHOLOGY
卷 38, 期 3-4, 页码 185-196出版社
ELSEVIER SCIENCE BV
DOI: 10.1016/S0169-555X(00)00080-5
关键词
braided rivers; anabranches; thread flow
Considerable progress has been made recently in characterising the patterns displayed by the anabranches of braided rivers. However, the physical processes of sediment scour, transfer and deposition that govern the generation and evolution of anabranch channels remain largely unexplained. Direct measurement of three-dimensional flow fields and morphological evolution of the anabranches in the braided Brahmaputra-Jamuna River, Bangladesh, were undertaken to investigate the interactions between fluvial processes and anabranch morphology. These data were used to elucidate the circumstances leading to the bifurcation of a single channel, which is a topic of fundamental importance to understanding the physical processes responsible fur braiding. Results indicate that division of the velocity field into multiple threads within a single channel precedes a division in the cross-sectional morphology of the channel and appears to be a necessary prerequisite for development of a bifurcation. An empirical relationship was established to discriminate between channels with single and multi-thread velocity fields, based on the depth-to-width ratio and specific energy of the flow at a representative channel cross-section. This function requires further validation, but could be used to predict the conditions under which a single channel is likely to bifurcate to produce two anabranches. (C) 2001 Elsevier Science B.V. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据