natural levee

基本解释

A gap eroded by flood waters cutting through a natural levee. Cracks in the top of a glacier.
洪水切割天然堤所侵蚀出的缺口称为决口。冰川顶部的裂隙可称冰隙。
www.infopetro.com.cn
There are 7 sedimentary microfacies that can be recognized, including underwater distributive river course, estuarine bar, submerged natural levee, etc.
研究区识别出水下分流河道、水下分流河道堤泛沉积、河口砂坝、远河口砂坝、分流间湾、前缘席状砂等微相。
The natural levee, crevasse splay and overbank sand are difficult to be effective reservoir for their content of mud-bearing silt, silty mud and unmixed mud.
天然堤、决口扇、溢岸砂多为含泥粉砂、粉砂质泥和纯泥，很难成为有效储层。

Dr. VIRGINIA BURKETT (Chief, Forest Ecology Branch, National Wetlands Research Center, U.S. Geological Survey): For example, where we have artificial fill, the subsidence rates are much more rapid than they are on the natural levee deposits.
NPR: Satellite Imagery Shows a Sinking New Orleans