Abstract
Usually, the study of inland lake sediments is mostly limited to sedimentary features, isotopes, grain size, magnetization rate, etc., while the study of material composition and weathering characteristics of inland lake sediments can deepen the understanding of chemical weathering of inland lakes. In this thesis, four positive chemical weathering indicators and one negative chemical weathering indicator were selected to study the surface and deep sediments of Chaohu Lake, China, and to analyze the chemical composition of Chaohu Lake sediments and the chemical compositional characteristics of source rocks in the Chaohu Lake basin. The mean CIA of Chaohu Lake sediments is <65, indicating that the Chaohu Lake Basin has a weak chemical weathering intensity, and the paleoclimate belongs to a cold, dry environment. The characteristics of Th/U, Sc/Th, Rb/Sr, Na2O/K2O, CaO/MgO and OC/N of the Chaohu sediments reflect the paleoclimate characteristics and the chemical composition of the source rocks in the Chaohu basin. The CIA, CIW, PIA, and CIX of Chaohu Lake sediments and the related chemical compositions as well as the ratios, showed significant positive or negative correlation or no correlation, which can correspond to the paleoclimate information of Chaohu Lake sediments and the distribution characteristics of the acquired chemical compositions, whereas WIP, a negative indicator of chemical weathering, did not show consistent correlation with the related chemical compositions as well as the ratios, which is not of significant research significance. To study the chemical weathering characteristics of Chaohu Lake sediments, it is necessary to combine with the geological characteristics of the lake basin, especially to analyze the chemical composition of rocks in the lake basin, and also to study the inlet rivers of inland lakes in order to analyze the chemical weathering characteristics of the sediments.