关键词: 微量元素, 地球化学特征, 物源意义, 东海陆架

Abstract:

The geochemical information from trace elements of the continental shelf sediment from East China Sea is a significant indicator to the stratigraphic division and provenance analysis. The trace elements of sediments derived from drillhole SFK1(82.90 meters in depth) which was located at Xihu depression in the continental shelf of East China Sea were analyzed and their provenances were discriminated. According to the changing law of trace element contents and their ratios，the sediments from drillhole SFK1 can be divided into eight layers, which reflect the fluctuation of sea level and the change of sediment sources in East China Sea since the late last interglacial cycle (warm period).  Combined with factor analysis, the scatter diagrams of U/Th vs. (Zr+Hf)/(Al2O3+TiO2) and Th/Co vs. TiO2/Zr were drawn to determine the material source of sediments from drillhole SFK1. The results revealed that the material sources of sediments mainly come from the Changjiang River, and sediments in the middle part of the drillhole were apparently influenced by materials from the Yellow River. The results also indicated that in the case of unchanging sediment sources, the changes of climate and sedimentary environment had little effect on transformation and redistribution of chemical elements of sediments in the study area.

Key words: trace element, geochemical characteristic, source significance, continental shelf of the East China Sea