Stabilizing self-organized structures in gravel-bed stream channels: Field and experimental observations

被引:258
作者
Church, M [1 ]
Hassan, MA
Wolcott, JF
机构
[1] Univ British Columbia, Dept Geog, Vancouver, BC V6T 1Z2, Canada
[2] Univ So Calif, Hlth Sci Adm, Los Angeles, CA 90089 USA
关键词
D O I
10.1029/98WR00484
中图分类号
X [环境科学、安全科学];
学科分类号
08 ; 0830 ;
摘要
Stable reticulate structures, which we call "stone cells," have been observed in cobble-gravel channel beds with low bed material transport rates. Experiments show that such structures develop simultaneously with the armor layer during an extended period when flows do not exceed the Shields threshold by more than similar to 2 times, so that bed material transport is low. They are constructed by particles moving from less stable positions into more stable configurations against each other. Intermediate developments include clusters and stone lines. They reduce sediment transport by orders of magnitude and are evidently a major stability-promoting mechanism in gravel channels. The timescale for their development suggests that the boundaries of many gravel-bed channels are not in equilibrium with recent competent flows but reflect the history of recent "dominant" flows.
引用
收藏
页码:3169 / 3179
页数:11
相关论文
共 52 条
[1]  
AHMED MME, 1989, THESIS COLO STATE U
[2]   PHASE DIFFERENCES BETWEEN BED CONFIGURATION AND FLOW IN NATURAL ENVIRONMENTS, AND THEIR GEOLOGICAL RELEVANCE [J].
ALLEN, JRL .
SEDIMENTOLOGY, 1973, 20 (02) :323-329
[3]   INTRUSION OF FINE SEDIMENTS INTO A STABLE GRAVEL BED [J].
BESCHTA, RL ;
JACKSON, WL .
JOURNAL OF THE FISHERIES RESEARCH BOARD OF CANADA, 1979, 36 (02) :204-210
[4]  
BLUCK BJ, 1987, I BRIT GEOGRAPHERS S, V17, P159
[5]   THE HYDRODYNAMICS OF PARTICLE CLUSTERS AND SEDIMENT ENTRAINMENT IN COARSE ALLUVIAL CHANNELS [J].
BRAYSHAW, AC ;
FROSTICK, LE ;
REID, I .
SEDIMENTOLOGY, 1983, 30 (01) :137-143
[6]  
BRAYSHAW AC, 1985, GEOL SOC AM BULL, V96, P218, DOI 10.1130/0016-7606(1985)96<218:BMAETI>2.0.CO
[7]  
2
[8]   FRICTION ANGLE MEASUREMENTS ON A NATURALLY FORMED GRAVEL STREAMBED - IMPLICATIONS FOR CRITICAL BOUNDARY SHEAR-STRESS [J].
BUFFINGTON, JM ;
DIETRICH, WE ;
KIRCHNER, JW .
WATER RESOURCES RESEARCH, 1992, 28 (02) :411-425
[9]  
Church M., 1978, CANADIAN SOC PETROLE, V5, P743
[10]  
DALCIN R, 1968, SEDIMENT GEOL, V2, P233