摘要
为研究银额盆地下白垩统巴音戈壁组含油页岩岩系有机质富集的有利条件,通过野外露头踏勘、岩性观察、矿物学分析和元素地球化学测试等工作,综合开展了研究区地球化学特征与有机质富集条件研究。X-衍射分析表明样品中主要为陆源碎屑矿物和黏土矿物,黏土矿物中高岭石含量较少,油页岩中还含有少量的方解石和白云石。TOC、S1+S2等有机地球化学指标显示油页岩有机质类型主要为Ⅰ型和Ⅱ1型,其他泥页岩为Ⅱ2型和Ⅲ型,整体处于低熟-未熟阶段。Sr/Cu(3.24~390.70)、Sr/Ba(0.17~4.77)和V/(V+Ni)(0.39~0.84)等无机元素地球化学特征参数综合分析表明,银额盆地巴格毛德地区下白垩统巴音戈壁组二段含油页岩岩系沉积时期整体为炎热干旱与温暖湿润交替发育的气候环境,淡水-咸水交替出现的还原水体环境。其中较炎热干旱的半咸水-咸水环境有利于有机质富集,形成高品质油页岩。
In order to study the favorable conditions for organic matter enrichment in the oil shale-bearing successions of the Lower Cretaceous Bayingebi Formation in Yin’ e Basin,a comprehensive study was undertaken through outcrop survey,lithological observation,mineralogical analysis and element geochemical testing.X-ray diffraction analysis shows that the samples mainly consist of terrigenous clastic minerals and clay minerals.The clay minerals comprise minor kaolinite,and a small amount of calcite and dolomite occur in oil shale.TOC,S1+ S2 and other organic geochemical indexes show that the organic matter in oil shale are mainly type I and type Ⅱ1,type Ⅱ2 and type Ⅲ in other shale,they are in the stage of low maturity and immature as a whole.The comprehensive geochemical analysis of inorganic elements such as Sr/Cu( 3.24 ~ 390.70),Sr/Ba( 0.17 ~ 4.77) and V/( V + Ni)( 0.39 ~ 0.84) shows that the oil shale-bearing successions of the Lower Cretaceous second member of Bayingebi Formation in the Bagemaode area of Yin’ e Basin was deposited in alternative hot and drought climate and warm humid climate,and a reducing environment of fresh water and saline water alternation.The hot and arid climate and saline-brackish water environment is conducive to the enrichment of organic matter and the formation of highquality oil shale.
作者
武昕普
柳蓉
张坤
赵康安
韩佳兵
WU Xin-pu;LIU Rong;ZHANG Kun;ZHAO Kang-an;HAN Jia-bing(College of Earth Sciences,Jilin University,Changchun 130061,China;Key Laboratory of Oil Shale and Coexistent Energy Minerals of Jilin Province,Changchun 130061,China;Key Laboratory for Evolution of Past Life and Environment in Northeast Asia(Jilin University),Ministry of Education,Changchun 130026,China)
出处
《世界地质》
CAS
2019年第4期1021-1031,共11页
World Geology
基金
吉林省重点科技研发项目(20180201077SF)
关键词
银额盆地
下白垩统
巴音戈壁组
含油页岩岩系
有机质富集
地球化学特征
Yin’ e Basin
Lower Cretaceous
Bayingebi Formation
oil shale-bearing
organic matter enrichment
geochemical characteristics
