高邮凹陷断裂对始新统油气成藏的控制作用  

Control of Faults on Eocene Hydrocarbon Accumulation in Gaoyou Depression of Subei Basin

作　　者：娄国泉[1] 

机构地区：[1]中石化江苏油田分公司物探技术研究院,江苏南京210046

出　　处：《石油天然气学报》2011年第1期1-5,164,共5页Journal of Oil and Gas Technology

基　　金：国家自然科学基金项目(40772089)

摘　　要：高邮凹陷是苏北盆地的重要含油气区,该区断裂发育,始新统油气的分布具有明显的分带特征,断裂活动速率的差异对始新统油气的输导和保存具有十分重要的控制作用。通过对源岩生烃历史的模拟与始新统油气充注历史的研究,确定始新统油气的主要成藏期;进而运用断裂活动速率的方法,综合分析在油气充注期,不同区带的断裂对始新统油气成藏的控制作用。研究表明,高邮凹陷深凹带内的油气藏主要分布在微弱活动断裂附近(活动速率<10m/Ma),强烈活动断裂面(活动速率>25m/Ma)主要起油气垂向上的输导作用,不利于油气的聚集和保存;而北斜坡带断裂活动十分微弱(活动速率<5m/Ma)不具备沿断层面直线式输导油气的能力,油气只能通过断裂-砂体的有效组合,实现螺旋式垂向运移,后在始新统圈闭内聚集成藏。Gaoyou Depression was an important oil-bearing area in Subei Basin.There faults were developed,the oil distribution of the Eocene epoch had obvious zoning characteristics in each area,the difference in fault activity ratios(FAR) was important for Eocene oil migration and accumulation.Through modeling the history of oil-generation for the source rock and studying the history of the oil filling,the major hydrocarbon filling stages for Eocene reservoirs were determined.In addition,the control function of faults in different areas on Eocene hydrocarbon accumulation was integrally analyzed at the major hydrocarbon filling stage by using faulting activity ratios(FAR).Studies show that the oils in the deep-sag are generally distributed near weak active faults(FARs <10m/Ma),while intense activity fault surfaces(FARs>25m/Ma)is the beneficial petroleum migration area,which is non-beneficial for hydrocarbon accumulation.At the same time,the fault activities are lower in the northern slope(FARs<5m/Ma),which are not good for oil migration upward along the fault surfaces linearly.Therefore,oil in this area can only migrate upward spirally by the effective collocation of faults and sands,and then accumulate in the Eocene traps.

关 键 词：断层活动 源岩生烃史 油气充注史 油气成藏 高邮凹陷 

分 类 号：P618.13[天文地球—矿床学]