油藏底水与隔夹层对原油生物降解程度的控制效应  

Control Effects of Petroleum Biodegradation Degree by Bottom Water and Intercalation within Oil Reservoir

作　　者：江凯禧[1,2] 何文祥[2] 彭丽 肖七林[2] 陈祖林[2] 郭清正[1] 向念[1] 

机构地区：[1]中海油能源发展股份有限公司工程技术分公司非常规技术研究院,天津300452 [2]长江大学地球环境与水资源学院,湖北武汉430100 [3]中海油实验中心,天津300452

出　　处：《地球科学（中国地质大学学报）》2015年第11期1846-1857,共12页Earth Science-Journal of China University of Geosciences

基　　金：国家科技重大专项(No.2011ZX05033004-003)

摘　　要：系统剖析流花11-1礁灰岩油藏储层烃类的生物降解特征,揭示油藏底水与隔夹层对原油生物降解程度具有显著控制效应,这使得油藏原油生物降解程度及其分布预测更加复杂化.研究发现,流花11-1油藏具有统一的油水界面,油源类型单一,原油成熟度较高且分布较窄,可能为短期快速充注所形成的油藏.原油普遍遭受生物降解,降解程度均小于6级.垂向上,隔夹层虽可引起局部储层烃类降解程度的倒转,但单井油柱生物降解等级仍以储层与油水界面的距离为主要控制因素,表现为降解程度由顶部向底部呈明显梯度变化,油藏底水控制效应明显.横向上,油藏降解程度的差异主要由隔夹层控制下储层内原油与活跃底水的接触程度不同导致.在隔夹层密集发育区流体运动受阻,进而使微生物营养物质供应不足,代谢物质交换不畅,原油降解程度相对较低.在上述研究的基础上,建立了油藏底水与储层非均质性对原油生物降解程度的控制效应模型,并探讨了该方法在稠油油藏开发中的应用.The research of the controls on the degrees of petroleum biodegradation within heavy oil reservoirs will benefit heavy oil reservoirs developing optimization and enhancing recovery efficiency.The characteristics of biodegradation of the saturated hydrocarbon for core extracts from the Liuhua11-1reef reservoir are analyzed in this study,and the results show that bottom water and intercalation within the oil reservoir can significantly control the degree of petroleum biodegradation and affect the prediction of oil physical property.Liuhua11-1reservoir has the one oil-water contact（OWC）,with the hydrocarbon generated from the same source rock at similar high maturity and suffered from biodegradation less than level 6.Although the intercalations may lead to the occurrence of inversion of biodegradation level of oil columns,biodegradation level is mainly controlled by the vertical distance from its in situ place to OWC,which is characterized by the biodegradation degree increasing from the top of oil columns to the bottom with excellent gradient variations.Laterally,the biodegradation level varies significantly within the reservoir.It is mainly dominated by the extent of oil-water-contact area controlled by intercalations.And intercalations also lead to the insufficient supply of nutrients and poor metabolism exchange because the fluid flow can hardly pass in the area where intercalations develop,which results in lower biodegradation.A model of control effects of petroleum biodegradationdegree by bottom water and reservoir heterogeneity within the oil reservoir is established,and its application in heavy oil reservoir development is discussed in this paper.

关 键 词：生物降解 隔夹层 降解倒转 底水控制 稠油开发 石油地质. 

分 类 号：P593[天文地球—地球化学] P618.13[天文地球—地质学]