| 1. | The sediments of the incised valleys show an upward - fining succession , and can be grouped into four sedimentary fades : gravel lag - deposit of in - channel to partly over bank sediments of a meandering river , flood plain - estuary , estuary - shallow marine , and estuary sand bar , based on lithology , paleontology , and sedimentary textures and structures 根据岩石学、沉积结构和沉积构造特征,本区下切河谷充填沉积物具有向上变细的沉积层序,可以划分为4个沉积相类型:河床滞留沉积物到部分曲流河沉积体系的边滩沉积、河漫滩河口湾沉积、河口湾浅海沉积和河口湾砂坝沉积。 |