东营凹陷岩性油气藏混源相对贡献及石油地质意义  

QUANTITATIVE PREDICATION AND SIGNIFICANCE OF MIXED OILS FOR LITHOLOGIC OIL POOL IN THE DONGYING DEPRESSION OF THE BOHAI BAY BASIN

作　　者：李素梅[1] 庞雄奇[1] 姜振学[1] 邱桂强[2] 高永进[2] 

机构地区：[1]中国石油大学油气资源与探测国家重点实验室,北京102249 [2]中国石油化工股份有限公司胜利油田分公司,山东东营257015

出　　处：《石油实验地质》2009年第3期262-269,共8页Petroleum Geology & Experiment

基　　金：国家自然科学基金项目(#40772077/D0206)

摘　　要：采用地球化学方法,对渤海湾盆地东营凹陷沙三中（Es3^M）岩性型隐蔽油气藏进行了混源相对贡献定量研究。结果表明,牛庄洼陷Es3M油气藏中沙四段成因原油的贡献约为28%～85%（均值58.5%～67.7%）;中央隆起带Es3^M油气藏沙四段成因原油的贡献约为9%～81%（均值32.4%～53.6%）。观察到牛庄洼陷靠近深切断层的原油中沙四段成因原油的贡献量高于远离断层的原油。东营凹陷沙三段砂岩透镜体岩性油气藏中高丰度沙四段＂异地源＂原油的混源定量结果表明,透镜体岩性油气藏不完全受围岩油源条件控制,隐蔽输导体系与常规运移通道可能联合控制油气运移;透镜体油气藏＂自生自储＂成藏模式的传统观点有待修正,暗示东营凹陷等断陷盆地生油中心广泛分布的岩性油气藏潜伏着巨大的深部油气勘探潜能。定量结果还表明,牛庄洼陷具备为南斜坡提供足够的沙四段成因成熟油气的条件。东营凹陷沙四段源岩的油气潜能可能需要重新评价。Normal geochemical approaches were utilized in quantitative predication of the proportion of the mixed orls derived from Third （Es3）and Fourth （Es1） Member of Paleogene Shahejie Formation and accumulatech in middle interval of the Es3（Es3^M） in the Dongying Depression of Bohai Bay Basin, where subtle traps are primarily of lenticular basin--floor turbidite sands encompassed in mudstones mostly developed in the depression. The result shows that about 28%-85% of the mixed oils were derived from the Es interval with averaged level up to 58.5%-67.7% ira the Niuzhuang Sag, and about 9%-81% were Esederived oils in the Central Uplift of the depression （the average is up to 32.4%-53.6%）. It was observed that there are much more Es4 derived oils located nearby where deep faults developed. The fact theft high concentration of the Es1 derived oils with long migration distances discovered in the Es3^M subfie lithologienl traps in the Niuzhuang Sag suggests that surrounding source rocks might be not necessary having a full controlling on hydrocarbons supply of a subtle trap, and subtle migration pathway should play an important role in oil migration. The traditional opinion that hydrocarbons in situ accumulation in lenticular traps with short migraion distance from surrounding source rocks should be revised. It is suggested that there is great petroleum potontial in the depo-center of rifted basins in Eastern China, and the Niuzhuang Sag is capable to supply normal Es1 derived oils for the pools in the South Slope, which has been proved by the high proportion of the Es1 derived ods mixed in the oils of the Wangjiagan Oilfield. The petroleum potential of the Es4 member in the Dongying Dopression should be reevaluated.

关 键 词：混源油 混源定量 岩性油气藏 沙河街组 东营凹陷 渤海湾盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探]