中太平洋PC5222孔岩芯地球化学特征及物源探讨

通过对中太平洋PC5222孔45个岩芯样品进行常微量元素的测试分析与研究,发现元素含量在垂向上有4次比较明显的变化。早期沉积物中,随着Al2O3、Fe2O3、K2O、MnO、TiO2、CaO、CaCO3含量的增加,SiO2含量呈递减趋势;晚期变化不明显。元素的相关性分析和R型因子分析表明,Al2O3、Fe2O3、K2O、MnO、TiO2之间存在明显的正相关关系,而与SiO2为负相关。前者主要受陆源碎屑沉积的影响,后者与生物作用及火山活动有关。进一步探讨了晚渐新世沉积环境的演变规律。

Geochemistry and provenance of the PC5222 drill cores from the mid-Pacific Ocean

The analyses of the major and trace element contents in 45 pieces of core samples from the PC5222 drill hole in the mid-Pacific Ocean has disclosed that vertically,there are marked changes in element contents in different burial depths of sediments.The SiO2 contents decrease with the increase of the contents of Al2O3,Fe2O3,K2O,MnO,TiO2,CaO and CaCO3 in the early sediments.The things are different in the late sediments.The element correlation analysis and R-mode factor analysis indicate that there is a markedly positive correlation between the contents of Al2O3,Fe2O3,K2O,MnO and TiO2 while a negative correlation with the SiO2 contents.The former are influenced by the terrigenous clastic sediments,and the latter by the organic action and volcanic activity.The evolution of the sedimentary environments during the late Oligocene is also explored.