论文部分内容阅读
在层序地层学和沉积学研究的基础上,通过相关性分析,优选出Sr/V、Cd/Ca、Zr/Rb 3组元素地球化学指标,分别对中上扬子建南地区侏罗系自流井组东岳庙段的古气候条件、古生产力、以及古水动力条件开展分析,探讨研究区目的层有机质在层序地层格架内发育的成因机制。研究表明:与其他湖盆沉积的有机质发育特征相比,中上扬子建南地区侏罗系东岳庙段的湖相沉积在层序地层格架内有机质发育规律具有独特性,其低位体系域有机质非常发育,而湖扩体系域有机质较发育,高位体系域有机质最不发育,在沉积微相中,低位体系域浅湖亚相沉积有机质比低位体系域滨湖亚相沉积中的有机质更发育;而造成有机质差异性发育的主要控制因素是古生产力和有机质的保存环境。
Based on the study of sequence stratigraphy and sedimentology, the elemental geochemical indicators of Sr / V, Cd / Ca and Zr / Rb3 groups were optimized by correlation analysis, and the geochemical characteristics of the Jurassic artesian well in Jiannan area, Paleoclimatic conditions, paleoproductivity and palaeo- hydrodynamic conditions of the Dongyuemiao section of the study area are analyzed to explore the genesis mechanism of the development of organic matter in the sequence stratigraphic framework in the study area. The results show that the lacustrine sediments of the Jurassic Dongyuemiao Formation in the Jiannan area of the Upper Upper Yangtze have a unique characteristic of organic matter development in the sequence stratigraphic framework as compared with the organic matter developed in other lake basins. The organic matter in the lacustrine system is more developed and the organic matter in the upper system tract is the least developed. In the sedimentary microfacies, the organic matter in the shallow lacustrine sediments of the lowstand system tract is more developed than that of the lowermost lacustrine sediments in the lowerstand system tract. The main controlling factors that cause the development of organic matter are paleoproductivity and organic matter preservation environment.