Abstract: Based on the core observation and analytical data, the provenance of the Member 2 and 3 of the Upper Cretaceous Nenjiang Formation in Northern Songliao Basin was estimated according to the mineral content of sedimentary rocks, planar distributing of sandstone, ZTR index of heavy mineral and mudstone color distribution. The results show that the provenance of the Member 2 and 3 of Nenjiang Formation changes with time, but the change is small. The sediments of the Member 2 of Nenjiang Formation are mainly derived from the eastern provenance, whereas the sediments of the Member 3 of the Nenjiang Formation are derived from the eastern and northeastern provenances. Such a provenancial change might be aroused by the uplift of strata in the north area. During the deposition of the Member 2 and 3 of the Nenj iang Formation, three main provenances exist in Northern Songliao Basin: the northeastern source area, the eastern one and the western one. The eastern provenance dominates the sediments of the Member 2 and 3, while the latter Member 3 is dominated by both the eastern and the northeastern provenance. And the western provenance exists during the latter Member 3, but its incidence is small.

Key words: Northern Songliao Basin, Upper Cretaceous, Member 2 and 3 of the Nenjiang Formation, provenance analysis

摘要： 通过岩芯观察描述以及分析化验资料的综合分析, 从岩石矿物成分、砂体平面展布、重矿物组合以及锆石-电气石-金红石指数(ZTR 指数) 、泥岩颜色区域分布等方面对物源方向进行了判断。综合分析表明: 松辽盆地北部嫩江组二、三段沉积时期物源随时间变化有所变化, 但变化不大。嫩江组二段沉积时期物源主要来自东方; 嫩江组三段沉积时期物源除东部来的物源外, 东北部物源对盆地北部物源体系也参与贡献, 物源的变化可能是由于嫩二段晚期盆地北部地层隆起。松辽盆地北部在嫩江组二、三段时期主要存在着 3 个方向的物源: 东北、东部以及西部物源。嫩江组二、三段沉积时期, 东部物源为主要物源, 在嫩江组三段沉积的中后期, 东北向物源出现并与东部物源共同起主导作用。西部物源在嫩江组三段沉积的中晚期出现, 影响范围小。

关键词: 松辽盆地北部, 上白垩统, 嫩江组二, 三段, 物源分析