东北地区侏罗-白垩系界线划分对比问题的讨论

COMPARISON OF THE DELIMITATION OF JURASSIC-CRETACIOUS IN NORTHEAST AREA OF CHINA

在分析东北地区侏罗 白垩系界线划分对比研究现状的基础上 ,探讨了界线划分的标准与方法 ,对饶河地区东安镇、三江盆地绥滨坳陷、冀北地区大北沟等界线上、下 3条有连续沉积的剖面和松辽、辽西、海拉尔、鸡西、虎林等 5条非连续沉积的剖面进行了研究 ,以双壳类Buchia化石、沟鞭藻化石和孢粉化石等为主要媒介 ,并结合岩性对东北地区海、陆相侏罗 白垩系界线进行了划分与对比。饶河地区划分在上、下东安镇组之间 ,三江盆地划分在滴道组和东荣组之间 ,冀北地区划分在大北沟组上、下段之间 ,虎林盆地划分在七虎林组和下云山组之间 ,松辽盆地、辽西地区、海拉尔盆地、鸡西盆地划分在火石岭组、义县组、阿尔公组、滴道组之下 ,从而解决了东北地区侏罗

This paper analyzes the comparative study on the delimitation of Jurassic Cretaceous in northwest area and discusses the criteria and method of the delimitation. It studies 3 continuous sedimentary profiles above and under the bound of Dong'an town in Raohe area, Suibin depression in Sanjiang Basin and Dabeigou in Jibei area and 5 discontinuous sedimentary profiles of Songliao, Liaoxi, Hailaer, Jixi and Hulin. The delimitation and comparison of marine and non marine Jurassic Cretaceous boundary line is carried out by taking Buchia fossil of Bivalvia, dinoflagellate fossil and spore fossil as the main media and combining the lithology. Raohe area is between upper and lower Formation Dong'an town Formation, Sanjiang Basin is between Didao Formation and Dongrong Formation, Jibei area is between the upper and lower member of Dagou Formation, Hulin Basin is between Qihulin Formation and lower Yunshan Formation, and Songliao Basin, Liaoxi area, Hailaer Basin and Jixi Basin are under Huoshiling Formation,Yixian Formation,Aergong and Didao Formation. It resolves the delimitation and comparison of Jurassic Cretaceous boundary line in northeast area.