Holocene sedimentary systems on a broad continental shelf with abundant river input: process–product relationships

Abstract

AbstractThe region consisting of the Bohai, Yellow and East China seas represents a typical wide continental shelf environment with abundant terrestrial sediment supply. Here, a variety of sedimentary systems have been formed during the Holocene period. These systems have unique characteristics in terms of spatial distribution, material composition, deposition rate, and the timing and duration for their formation, which are related to active sediment-transport processes induced by tides and waves, shelf circulations, and sediment gravity flows. The sedimentary records contained within the deposits have a high temporal resolution, but each with a limited temporal coverage. However, if these records are connected, then they may form a complete archive for environmental change studies. In the field of process–product relationship studies, the mid-Holocene coastal deposits on the Jiangsu coast, the early–middle Holocene sequences of the Hangzhou Bay, the Holocene mud deposits off the Zhejiang–Fujian coasts and the other mud areas over the region are of importance. These systems may be understood by identifying the material supply (from both seabed reworking during the sea-level rise events and river discharges), transport-accumulation processes, the formation of sediment sequences and the future evolution of the sediment systems, for which numerical modelling becomes increasingly important.