Evolution of abandoned deltaic river channel−A case from the Diaokou channel of the Yellow River

Abandoned channels are one of the major components of a deltaic system, which contains valuable information related to tectonism, hydrology, sea-level fluctuation and environmental changes of the catchment. Comparing to the study of filling process of abandoned channels on land, which are well studied in the past decades, little research has been devoted to the tidal-dominated abandoned channels. The Diaokou River channel was fully abandoned in 1976 by an artificial construction separating it from the main course of the Yellow River. With the support of landsat images, bathymetric surveys and elevation data of the abandoned Diaokou River channel, the evolution of this tide-dominated abandoned channel is documented in this study. Since abandonment, about 0.3～2.0 meters of filling sediment have deposited in the channel, with along-channel and landward decrease in sedimentation. Marine dynamics is the main force to control the evolution of abandoned channels. The severe erosion near the abandoned channel mouth, as a source of sediments, has made the channel shortening gradually.