新疆柯坪地区沙井子组时代及界线探讨

Discussion on geological age and stratigraphic boundary of Shajingzi formation in Kapin of Xingjiang area

新疆柯坪地区沙井子组是古生界最高层位,研究了其时代的归属.依据在露头剖面所采集到的植物和孢粉化石,结合介形类、双壳类化石资料,应用生物地层和岩石地层学方法,确认沙井子组的时代应属晚二叠世.依据剖面岩性特征和接触关系,确定了沙井子组的顶、底界线.底界以开派兹雷克组的玄武岩层顶面为界,顶界以第三系的不整合面为界.

According to biostratigraphy and lithostratigraphy, the geologic age of Shajingzi formation in Kapin region of Xinjiang area is determined on the basis of the selected data from plant and spore pollen fossils combined with ostracoda and bivalve fossils. The Shajingzi formation belongs to upper Permian. Considering the lithologic sections and their contacting features, the lithologic boundaries of the upper and lower ends of the formation are established. The lower boundary is the top of basalt of Kaipaizileke formation, and the upper boundary is the unconformity surface of tertiary system.