新疆伊宁凹陷三叠纪地层研究新进展

Research progress of Triassic strata in Yining depression,Xinjiang

在前人研究的基础上,综合运用岩石地层学、生物地层学原理与方法,从钻井和野外露头剖面入手,根据新取得的古生物化石资料,结合岩性特征、构造运动,对伊宁凹陷三叠系岩石地层、生物地层进行了研究,首次认为伊宁凹陷缺失下三叠统,建议在该区引入准噶尔盆地西北缘岩石地层系统,三叠系自下而上发育中三叠统克拉玛依组,上三叠统白碱滩组;伊宁凹陷三叠纪孢粉化石可建立两个化石组合,组合Ⅰ为Aratrisporites-PiceaepollenitesChordasporites组合,时代为中三叠世,组合Ⅱ为Piceaepollenites-Dictyophyllidites-Colpetopollis组合,时代为晚三叠世。

On the basis of previous studies,by integrated use of rock stratigraphy,biostratigraphy principles and methods,starting from drilling and outcrop,according to new infor-mation obtained fossils,combined with lithology,tectonic movement,Yining depression Triassic rocks,the biostratigraphy has been studied for the first time.The results show that Yining depression is lack of Triassic,the introduction of the northwestern margin of the Junggar basin system has been proposed in the area of rock formations.From bottom to up,middle Triassic Karamay group and upper Triassic Baijiantan group were developed.Yining depression Triassic fossil pollen fossils can establish two combinations,combinationsⅠ for Aratrisporites-Piceaepollenites-Chordasporites portfolio,during Middle Triassic era,the combinationⅡ for Piceaepollenites-Dictyophyllidites-Colpetopollis portfolio,during the Late Triassic.