现代冲积河流的河型空间转化模式探讨

论述了现代冲积河流系统中常见河型的自然分布及转化特征,归纳了河型从上游向下游发生空间转化的 5种主要模式。这些河型转化模式发生的相对频率是不同的,其中从辫状河流向曲流河流转化的发生频率最大。文中通过具体实例总结了这些转化模式分别发生时的主要影响因素。

Spatial Variations of Channel Patterns

The formation of channel patterns and its characteristicsare important aspects in modern and ancient fluvial system studies, and thus become themain concern for hydraulic engineers, geomorphologists and sedimentologists. So far, thereare still some questions not clear in this area, for example, the classification ofchannel patterns, formation cause of anastomosing fluvial rivers, critical conditions ofevolution of some fluvial channel patterns, and further studies are still needed. Anotherproblem related to channel pattern is the transformation of the patterns. In the presentpaper, four ordinary patterns are discussed, which include the braided, meandering,anabranched (in which include the anastomosing) and straight patterns. Comprehensive studyto the spatial transformation of above channel patterns has significance not only formanagement of modern river and prevention of flood,but also for prospect and exploitationfor hydrocarbon and some mineral resources in ancient fluvial depositional systems.