COLLABORATIVE RESEARCH: Avulsion, Anastomosis, and Floodplain Sedimentation in Meandering Fluvial Systems

小行星9303851 本研究将研究撕脱的过程，即， 水流从现有河道中永久性地改道，以及在河流漫滩和冲积沉积物的演变中撕离的作用。 该方法将是协作性的，重点是数学建模实验以及现代和近现代河流洪泛区。 该项目将试图解决诸如撕脱的原因、撕脱通过洪泛区开始和传播的过程、洪泛区随后对撕脱的反应方式以及撕脱对洪泛区沉积物性质的影响等问题。 由于撕脱作用是河漫滩加积的必然结果，因此它在冲积沉积层序的演化中可能起着至关重要的作用，但迄今为止却未得到充分的重视，因为它很可能是一个主要的沉积过程，而不仅仅是旧河道废弃和新河道形成的一种机制。 当正确理解时，我们可能需要修改我们看待曲流带的起源和作用的方式，撕裂与漫滩洪水的相对重要性，以及洪泛平原沉积物的产生方式。

9303851 Slingerland This study will investigate the processes of avulsion, i.e., the permanent diversion of flow away from an existing river channel, and the role of avulsion in the evolution of river floodplains and alluvial sedimentary deposits. The approach will be collaborative, focusing on mathematical modelling experiments, and modern and near-modern river floodplains. The project will attempt to address such questions as the causes of avulsion, the processes by which avulsions initiate and propagate through flood basins, the manner in which floodplains subsequently react to avulsion, and the effects of avulsion on the character of floodplain deposits. Because avulsion is an inevitable consequence of floodplain aggradation, it may play a vital, and heretofore underappreciated, role int he evolution of alluvial sedimentary sequences because it is likely to be a major process of deposition instead of merely a mechanism by which old channels are abandoned and new ones formed. When properly understood, avulsions may require modifications in the way we view the origin and role of meander belts, the relative importance of avulsive vs overbank flooding, and the manners in which floodplain deposits are generated.