渤海湾盆地东营凹陷广利地区沙四上亚段物源体系及其对沉积的控制作用  

Provenance systems and their control on the sedimentation of the upper Es^4 in Guangli area of the Dongying Sag,the Bohai Bay Basin

作　　者：孙海宁[1,2] 万念明[1,2] 徐涛玉[3] 

机构地区：[1]中国科学院广州地球化学研究所,广东广州510640 [2]中国石油化工股份有限公司油田勘探开发事业部开发处,北京100728 [3]中国石油大学地球资源与信息学院,山东青岛266555

出　　处：《石油与天然气地质》2010年第5期583-593,共11页Oil & Gas Geology

基　　金：教育部新世纪优秀人才支持计划项目(NCET-06-0604);国家油气重大专项(2008ZX05051-002);国家自然科学基金项目(40972080)

摘　　要：岩石组分、元素地球化学以及砂砾岩百分含量等分析表明,渤海湾盆地东营凹陷广利地区沙河街组四段上亚段沉积时期存在南部和东北部两大物源体系,它们控制了广利地区沙四上亚段沉积时期的砂体成因类型与分布。沙四上亚段沉积早期以南部物源体系为主,主要发育曲流河三角洲-滨浅湖滩坝沉积体系;沙四上亚段沉积晚期以东北部物源体系为主,主要发育辫状河三角洲、扇三角洲等沉积体系;沙四上亚段沉积中期为两大物源体系的转换时期,南部和东北部物源体系共存,发育了重力流、牵引流交互沉积的多成因类型砂体。区内三角洲前缘由沿岸流改造形成的滩坝砂体是今后勘探的重点,应加大滩坝砂类岩性和构造共同控制的复合油气藏的部署和勘探。According to analyses of rock component, element geochemistry and sandy net-to-gross ratio, two provenance systems, namely the southern one and the northeastern one, are believed to exist during the sedimentation of the upper 4th member of Eocene Shahejie Formation （Es4） in Guangli area of Dongying Sag, the Bohai Bay Basin and they controlled the genetic types and distribution of sandbodies. In the early period of the sedimenta- tion of the upper Es4 ,the south provenance predominated,and there developed meander fiver delta and shallow lake-beach bars. While in the late period the sedimentation of the upper Es4 ,the northeast provenance predomi- nated,and there developed braided river delta and fan delta. In the middle period of the sedimentation of the upper Es4 ,the two provenance systems coexisted,and there developed sandbodies of multiple genetic types with alternating gravity flow deposits and traction current deposits. Beach bars resulted from modification of longshore current at the delta front should be important targets for further exploration. Exploration of lithologic-structural combination traps of beach bars types should be strengthened.

关 键 词：沙河街组 物源体系 沉积体系 广利地区 东营凹陷 渤海湾盆地 

分 类 号：TE122.2[石油与天然气工程—油气勘探]