陆相盆地坡折带的隐蔽油气藏勘探战略  

Exploration Strategy for Subtle Reservoirs in Slope Breaks of Terrestrial Basins

作　　者：李群[1] 王英民[2] 

机构地区：[1]石油大学盆地与油藏研究中心 [2]教育部石油天然气成藏机理国家重点实验室,北京102249

出　　处：《地质论评》2003年第4期445-448,共4页Geological Review

基　　金：国家重点基础研究发展规划项目(编号G1999043305)

摘　　要：本文从陆相坡折带的定义和分类入手,阐述了构造坡折带、沉积坡折带和侵蚀坡折带的成因以及对层序,尤其对低水位体系域和隐蔽油气藏的控制和影响。指出陆相坡折带与海相坡折带的区别主要表现在:①坡度不同:陆相盆地受构造作用(包括断裂作用)和短源快速沉积的影响,坡度较陡,碎屑物差异沉积明显。②坡折带特点不同:海相坡折带一般单一稳定,而陆相坡折带具有多级坡折的特点。在此基础上,对渤海湾盆地东营凹陷进行了研究。应用钻、测井及地震等资料,建立了东营凹陷沙三段中部地层的层序地层格架,共分为4个层序,并且每个层序可分为低水位体系域、水进体系域和高水位体系域。建立了储油单元与层序单元(尤其低水位体系域)对应关系。阐述了陆相盆地斜坡带沉积体系域中储集砂体类型和油气成藏机制,从而指导隐蔽油气藏勘探。On the basis of the definition and classification of terrestrial slope breaks, this paper discussed the genesis and sequence of slope breaks resulting from structure, sedimentation and erosion, especially subtle reservoirs controlled by lowstand systems tracts. The differences between terrestrial and marine slope breaks are:(1) the slope of a terrestrial slope break is steeper than a marine one, which is caused by structural movement and rapid terrestrial sedimentation from a close-by provenance; and (2) marine slope breaks are commonly mono-slope breaks, whereas terrestrial slope breaks are composed of several slope breaks. These were applied in the Dongy-ing Sag of the Bohai Bay Basin. We established a sequence framework composed of four sequences. These four sequences are all divided into lowstand systems tracts, advance systems tracts and highstand systems tracts. We also established the relationship between reservoirs and sequence units, especially lowstand systems tracts, and studied the types of sand bodies in systems tracts of terrestrial slope breaks and the mechanism for oil-gas reservoir formation.

关 键 词：层序地层学 坡折带 低水位体系域 隐蔽油气藏 陆相盆地 油气藏勘探 成藏机制 

分 类 号：P539.2[天文地球—古生物学与地层学]