福山凹陷南部缓坡流沙港组坡折带特征及对沉积、油气成藏的控制  

Characteristics of slope-breaks and its control on sedimentation and hydrocarbon accumulation of Liushagang Formation in gentle slope of south Fushan sag

作　　者：王观宏 黄传炎[1,2] 刘恩涛[1,2] 李媛[1,2] 潘松圻[1,2] 

机构地区：[1]中国地质大学(武汉)构造与油气资源教育部重点实验室,湖北武汉430074 [2]中国地质大学(武汉)资源学院,湖北武汉430074

出　　处：《中南大学学报（自然科学版）》2014年第5期1531-1541,共11页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(41272122);国家"十二五"油气重大专项(2011ZX05009-002-02)

摘　　要：分析坡折带的油源条件、储集条件、输导条件、封盖条件与圈闭条件,并对不同沉积时期不同坡折背景下的隐蔽油气藏类型及分布进行预测。研究结果表明,受海南隆起持续隆升和中部凹陷区持续沉降,及福山凹陷非对称拉伸应力的控制,在流沙港组沉积期,福山凹陷南部缓坡东、西部形成不同的坡折带类型:即西部受美台断层控制的断裂坡折带,东部受南部缓坡古地形控制的挠曲坡折带。南部缓坡坡折带控沉积作用受湖平面变化及物源供给的影响显著,流二段沉积期控制作用弱,到流一段沉积时期显著增强,坡折背景下流一段低位期和流二段的浊积体形成机理、发育规模及展布样式也存在差异;因坡度、坡折面延伸规模及坡降产生的可容纳空间大小的不同,断裂坡折带和挠曲坡折带控制了不同扇体发育规模及沉积相带纵向分异特征。南部缓坡坡折带是形成隐蔽油气藏富集带的有利地区。该研究结果将为福山凹陷油气藏勘探部署提供科学意见。The conditions of source rocks, reservoirs, transporting, sealing and traps were analyzed. The types and distribution of subtle reservoirs with various palaeogeomorphology backgrounds of slope-break in various sedimentary periods were predicted. The results show that affected by continuous uplift of the Hainan Uplift, continuous settlement of the depression area in the central of Fushan Sag and asymmetric tensile stress, two different structural slope-break types, including fault ramp zone affected by the Meitai Fault and flexure slope-break, are formed in the west and east of the gentle slope in south Fushan Sag respectively. The slope-breaks in the gentle slope are inner basin slope-breaks. Their control on sedimentary is affected by variations of the lake level and source supply significantly, which is weak in Liu 3 Member, and increased significantly in Liu 2 Member. The formation mechanism, scale and distribution of turbidite sandstone bodies are also different in different sedimentary period. Because of the discrepancy in gradient, extending range of the slope-breaks and accommodation space size, different kinds of slope-breaks show controllable variance on development scale of fan bodies and vertical distribution characteristic of sedimentary facies zone. The slope-breaks are favourable to form subtle reservoirs. The research results are of great significance to the deployment of oil and gas exploration.

关 键 词：坡折带 沉积体系 隐蔽油气藏 流沙港组 福山凹陷 

分 类 号：P539.2[天文地球—古生物学与地层学] TE121[天文地球—地质学]