DISTRIBUTION OF MAJOR ELEMENTS IN THE SEDIMENTS OF THE YANGTZE RIVER ESTUARY AND ADJACENT OFFSHORE AREAS AND ITS CONTROLLING FACTORS

Based on the major elements abundances of the sediment samples from 187 stations in the Yangtze River Estuary and its adjacent offshore areas,R-mode cluster analysis and R-mode factor analysis have been carried out for the major elements in the sediments. The main controlling factors were discussed. Al₂O₃,MgO,K₂O and Fe₂O₃ have similar distribution patterns, whereas SiO₂ is negatively correlated with these oxides. The distribution of CaO and CaCO₃ in the southeast parts of the Yangtze River Estuary and its adjacent area shows a clear link with the source materials related to the biogenic process, whereas the distribution of TiO₂ indicates the direction of sediment transportation. R-mode factor analysis could be used to reveal the main factors which control the element distributions in the surface sediments of the study area.