荣胜堡洼陷周边沙三段油气富集条件研究

Research on Hydrocarbon Accumulation Conditions of the Third Member of Shahejie Formation around Rongshengpu Subsag

大民屯凹陷沙三段是辽河油田重要的勘探层系,已累计上报探明石油地质储量占大民屯探明储量的50%,勘探程度极高,但沙三段区域储层砂体普遍发育,已发现油气分布的不均衡性决定了该区域具有较大的勘探空间。荣胜堡洼陷是大民屯凹陷最重要的生油洼陷,分析荣胜堡洼陷及其周边沙三段的油气藏类型及油气藏＂生、储、盖、圈、运、保＂等成藏条件,结果表明,构造对油气成藏控制作用明显,发育构造、岩性和构造-岩性油藏,油源主要来自Es34优质烃源岩,储盖组合配置关系良好,圈闭条件和输导条件是控制沙三段油气成藏的主要因素。以此为依据,在荣胜堡洼陷周边圈定了荣胜堡北胜29-胜31井区和荣胜堡下降盘两个勘探目标区,在建立精细的地层格架基础上,开展精细地质研究工作,采用老井试油和新井部署相结合的勘探方法,有利地拓宽了大民屯的勘探领域。

The third member of Shahejie Formation（Es3） of Damintun Sag is an important exploration horizon in Liaohe Oilfield.It has high exploration degree with the reported proven OOIP accounts for 50% of the proven reserves in Damintun sag.The sandbodies well developed in the reservoirs of Es3.The uneven distribution of petroleum indicates that there is large exploration potential in this area.Rongshengpu Subsag is the most important oil-generation one of the Damintun Sag.Types and ＂source-reservoir-cap-trap-migration-preservation＂ hydrocarbon accumulation conditions of the oil-gas reservoirs of Es3 in and around Rongshengpu Subsag were analyzed.The results show that the structure has great control on hydrocarbon accumulation,and structural,lithologic and structural-lithologic reservoirs were developed.Oil comes from good hydrocarbon source rocks in Es34.The reservoir-cap assemblage matches well.Trap and transportation control the hydrocarbon accu-mulation in Es3 mainly.Based on that,Sheng29-Sheng31 well block in the north of Rongshengpu and Rongshengpu downthrow side were determined as two exploration target areas around the Rongshengpu Subsag.Based on fine stratigraphic framework,fine geological study was carried out.The combination of oil testing in old wells and deploying new wells may broaden exploration field of Damintun Sag.