泌阳凹陷北部斜坡带生物降解油的油源对比  

Oil-source correlation for biodegraded oils in the north slope of the Biyang Depression

作　　者：李水福[1,2] 胡守志[1,2] 何生[1,2] 王华[1,2] 杨道庆[3] 林社卿[3] 罗家群[3] 

机构地区：[1]中国地质大学构造与油气资源教育部重点实验室,湖北武汉430074 [2]中国地质大学资源学院,湖北武汉430074 [3]中国石化河南油田分公司勘探开发研究院,河南南阳473132

出　　处：《石油学报》2010年第6期946-951,共6页Acta Petrolei Sinica

基　　金：国家自然科学基金项目(No.40902037);中央高校基本科研业务费专项资金项目(CUGL090219)联合资助

摘　　要：生物降解油尤其是严重生物降解油,其油源对比一直是个难点。针对严重生物降解油的常规生物标志化合物特征,提出用C29藿烷替代C30藿烷计算伽马蜡烷指数(伽马蜡烷/2×C29藿烷,暂称新伽马蜡烷指数),研究认为它更能反映生物降解油母质形成的水体环境。并用伽马蜡烷/2×C29藿烷和2×C24四环萜烷/C26长链三环萜烷作图版,可以将泌阳凹陷北部斜坡带不同层位原油很好地区分开,达到生物降解油的油源对比目的。油源对比结果,井楼和古城地区核三上段原油和核三下段原油主要源自其相应层段的源岩,新庄以核三上段油源为主,杨楼以核三下段油源为主。Oil-source correlation of heavy oils,especially for oils severely biodegraded,is not readily conducted by means of the conventional method.Based on characteristics of normal biomarkers for heavy-biodegraded oils,the present paper proposed a relationship of the abundance of low-molecular-weight steranes in the total steranes versus that of the corresponding triaromatic steranes in the total ones to indicate their alteration degree.In addition,C29αβ hopane instead of C30αβ hopane was suggested to calculate the gammacerane index（gammacerane/2×C29αβ hopane） that is tentatively called a new gammacerane index because it was believed that this new parameter might indicate more accurately the water conditions under which kerogens of biodegraded oils were formed.The result showed that different oils and source rocks from the Biyang Depression could be distinguished clearly by applying a plate of the gammacerane/2×C29αβ hopane ratio versus the 2×C24 tetracyclic terpane/C26 tricyclic terpane ratio,hence,the oil-source correlation for severely biodegraded oils from the north slope of the Biyang Depression was made successfully.Crude oils,which are in the upper and lower members of Eh3 from the area of Gucheng and Jinglou,were originated from the upper and lower members,individually.In addition,the crude oils in Xinzhuang were mainly from the upper member of Eh3,while the crude oils in Yanglou were mainly from the lower member of Eh3.

关 键 词：泌阳凹陷 北部斜坡带 生物降解油 新伽马蜡烷指数 油源对比 

分 类 号：TE112.114[石油与天然气工程—油气勘探]