【摘要】 为探究准噶尔盆地吉木萨尔凹陷中二叠统芦草沟组陆源碎屑岩的沉积环境、风化程度及物源,对该凹陷内的吉174井岩心样品中的泥岩进行主量元素和微量元素实验分析。研究了芦草沟组泥岩氧化还原敏感微量元素比值、化学蚀变指数(CIA)、稀土元素含量与比值特征、泥岩源区岩性分布和古构造背景。结果表明:吉木萨尔凹陷中二叠世水体为贫氧的弱还原-还原环境;碎屑颗粒从物源区到沉积盆地经历了低强度的风化与简单循环过程;研究区母岩以凹陷西南部依林黑比尔根山地区晚古生代花岗岩为主,有部分基性岩及古老沉积物混入,具有多源性;沉积构造背景属于大陆岛弧和活动大陆边缘环境。更多还原

【Abstract】 In order to explore the sedimentary environmental characteristics,weathering degree and provenance of the terrigenous clastic rock of the Middle Permian Luocaogou Formation in Jimsar sag of the Junggar basin,experiments on major elements and trace elements of the mudstones of the core samples of the J174 Well in the sag were carried out. The REDOX sensitive trace elements ratio,chemical alteration index( CIA),the content and ratio of the rare earth elements,the lithology distribution of the mudstone’s source area and paleotectonic setting were studied. The results show these as follows. The Permian water body of the Jimsar Sag is the weak reduction-reduction environment for poor oxygen; the detrital particles from the source region to the sedimentary basin experienced the low-intensity weathering and simple cycle; the mother rock of the research area is mainly composed of the late Paleozoic granites of the Yilinhabiergen Mountain,southwest to the Jimsar Sag,with mixture of some basic rocks and ancient sediments,which has the characteristics of multi-source; the sedimentary tectonic background belongs to continental island arc and the active continental margin environment.更多还原