Dynamic sedimentary environment and the provenance characteristics in Yangtze River Estuary-Hangzhou Bay and its adjacent waters

There is a complicated dynamic sedimentary environment in Yangtze River Estuary-Hangzhou Bay and its adjacent waters,which is affected by the material transport and eco-environment of waters.In this paper,grain size distributions,rate earth elements and platinum group elements were analyzed for surface sediments from the Yangtze River Estuary-Hangzhou Bay and its adjacent waters.The investigated area has been partitioned into eight dynamic sediment environment divisions with a triangular diagram advanced by Pejrup M:two estuarine modern depositional regions with intense hydrodynamics;two nearshore modern depositional regions with the interaction on different water masses;one frontal region in the continental shelf;two relict sedimentary regions influenced by modern material supply from the warm current and the coastal current;and one modern depositional region with cyclonic eddy.By comparing grain size distributions and hydrodynamic patterns in different dynamic sedimentary environment regions,sedimentary features were revealed under different hydrodynamic conditions and the provenance characteristics were recognized in a variety of depositional environment.