鄂尔多斯盆地陇东地区延长组原油地球化学特征及成因类型划分  

Geochemical characteristics and genetic types of crude oil from Yanchang Formation in Longdong Area,Ordos Basin

作　　者：柳广弟[1] 杨伟伟[1,2] 冯渊[2] 马海勇[2] 独育国[2] 

机构地区：[1]中国石油大学(北京)油气资源与探测国家重点实验室,北京102249 [2]中国石油长庆油田分公司,陕西西安710021

出　　处：《地学前缘》2013年第2期108-115,共8页Earth Science Frontiers

基　　金：国家科技重大专项"大型油气田及煤层气开发"项目(2011ZX05044;2011ZX05001)和"鄂尔多斯盆地大型岩性地层油气藏勘探开发示范工程"项目(2008ZX05044 1-3-2)

摘　　要：利用原油与岩样抽提物的族组成分离与定量分析、饱和烃色谱—色质、芳烃色谱—色质等分析测试资料,系统分析了陇东地区延长组原油的地球化学特征,并研究了原油的成因类型。研究表明,陇东地区延长组原油均为正常油,组分以饱和烃馏分为主;原油的母质来源为低等水生生物与陆源高等植物的双重贡献;形成环境为淡水—微咸水的水体环境、弱氧化—还原的沉积环境;原油为成熟油,属于烃源岩生烃高峰时期的产物。根据C30重排藿烷的相对含量,可将原油划分为3类,第Ⅰ类原油C30重排藿烷含量最低,第Ⅱ类原油C30重排藿烷含量中等,第Ⅲ类原油C30重排藿烷含量最高。其中第Ⅰ类原油最多,来自于长7油页岩,该类原油分布广泛,白豹、西峰、合水、华庆以及姬塬地区均以该类原油为主;第Ⅱ、Ⅲ类原油样品较少,与暗色泥岩关系密切,零星分布于镇北以北,西峰以东地区。The geochemical characteristics and genetic types of crude oils from Yanchang Formation of Long dong Area were studied by separation and quantitative analysis of group compositions, chromatogram and mass spectrometry of saturated hydrocarbon and aromatic hydrocarbon. The results showed that the oils are all nor real and the group composition is mainly saturated hydrocarbon. The source materials are dual contributions of lower hydrobiont and terrigenous higher plants. The environment is fresh to slight saline water and weak oxi dizing to reducing sedimentation. The oils are all mature, accumulated at the peak of hydrocarbon generation. According to The relative content of C30 rearrangement hopanes, the oils are divided into three genetic types. The C30 rearrangement hopane content of the genetic type I oil is lowest, that of the genetic type II oil is middle, and that of the genetic type III oil is highest. The oil samples of genetic type I coming from Chang 7 member oil shale are the most, which are widely distributed in Baibao, Xifeng, Heshui, Huaqing and Jiyuan Areas. While the oil samples of genetic type II and III coming from dark mudstone are fewer, which are dis tributed in the north of Zhenbei Area and the east of Xifeng Area.

关 键 词：原油 地球化学特征 成因类型 延长组 陇东地区 

分 类 号：P618.130.2[天文地球—矿床学]