沉积学报2025，Vol.43Issue(3)：880-893,14.DOI:10.14027/j.issn.1000-0550.2024.078
供源组分和流量对于曲流河形态变化的影响
An Experiment-based Study of the Effects of Source Composition and Discharge on Morphology Change in a Meandering River by Flume Sedimentary Simulation
摘要
Abstract
[Objective]River sediments are widely developed in natural strata,and meandering river sediments are an important part.The frequent channel migration that occurs during the development of meandering rivers results in a large number of lateral sedimentary deposits,complicating the superposition relationship of sand bodies at any par-ticular deposit site.The analysis of factors influencing meandering river morphology is a highly significant aspect of the study of paleoclimate evolution and continental weathering intensity,and therefore important in the exploration and development of oil and gas reservoirs.In previous research,the initial conditions necessary for generating a mean-dering river have been proposed following observation of modern river sediments and assessment of the effects of clay mineral content,vegetation cover and initial saturation of the river bed.However,because in nature the development of river sediments takes place over very long periods of time,the dynamic sedimentation process cannot be definitely determined by field investigation or by the examination of outcrop sections.The history of a meandering river is susceptible to the influence of a range of environmental factors,and supporting quantitative data is usually lacking.[Methods]In this experimental study,the effects of single factor conditions on channel migration and dam body formation were investigated by flume sedimentation simulation.Three sets of experiments incorporating different parti-cle size,water flow and clay mineral content were conducted,using high-precision 3D laser scanning to convert the data into a series of elevation models,enabling quantitative examination of the profile,structure and bed sediment changes.[Results](1)The particle size of the source sand directly affected the curvature of the river meanders.For constant clay content and constant discharge,smaller particle size resulted in the meanders of the river having broad-er curvature.Also,obvious differences in the structure of the bank collapse were observed for different particle sizes.(2)When the sediment input rate and transport rate were in dynamic equilibrium,the discharge rate affected the sediment transport balance and the force of flow impact on the riverbank caused the riverbank to continuously erode and expand outwards,and the channel developed a meandering river form.(3)The addition of clay minerals to the river bank materials improved the resistance of the river bank by lowering its permeability.When the source sand grain size and flow rate remained unchanged,greater clay mineral content lowered the width-to-depth ratio of the river channel.[Conclusions]This study clarifies the influence of sand grain size,water discharge and clay mineral content on the morphological properties of a meandering river,and provides quantitative basic data for the study of meander evolution.关键词
曲流河发育过程/水槽模拟实验/河流形态/沉积特征/河岸剥蚀现象Key words
meander development process/flume simulation experiment/river morphology/sedimentary characteristics/river bank denudation分类
天文与地球科学引用本文复制引用
洪瑞峰,唐明明,彭晨阳,熊思琛,解容..供源组分和流量对于曲流河形态变化的影响[J].沉积学报,2025,43(3):880-893,14.基金项目
国家自然科学基金项目(42072163)[National Natural Science Foundation of China,No.42072163] （42072163）
