塔河油田S80单元缝洞体分布规律及发育模式  

The fractured-vuggy structural model of S80 unit, Tahe oilfield

作　　者：李莹[1,2] 王怀洪 巩固 郭涛 宋宇 吕大炜[3] 

机构地区：[1]山东省煤田地质规划勘察研究院,山东泰安271000 [2]山东科技大学,山东青岛266590 [3]山东科技大学山东省沉积成矿作用与沉积矿产重点实验室,山东青岛266590

出　　处：《油气地质与采收率》2014年第6期30-32,36,共4页Petroleum Geology and Recovery Efficiency

基　　金：国家"973"计划"碳酸盐岩缝洞型油藏开采机理及提高采收率基础研究"(2011CB201001);山东省优秀中青年科学家科研奖励基金计划项目"大型陆表海盆地海侵事件沉积及事件古地理特征--以华北板块晚古生代盆地为例"(BS2011SF017)

摘　　要：S80单元是横跨塔河油田六区、七区的重要油气开发区块,采用石油地质学、沉积学与构造地质学交叉思路与方法,研究了S80单元缝洞体分布规律及发育模式。以岩溶缝洞体的形成原因及构造形态为依据,将研究区缝洞划分为落水洞、干流洞、支流洞和末梢洞4种类型。4种类型缝洞在表层岩溶带最为发育,落水洞沿构造低部位、斜坡带呈串珠状分布;渗流岩溶带发育一小部分末梢洞,连通程度受限;径流岩溶带以干流洞为主,干流洞主要沿平行或近平行于地层方向发育,在纵向上叠置分布。表层岩溶发育段分布范围广,且多表现为顺层发育;深部缝洞体条带特征明显,具暗河特征,与断裂的关系密切。S80单元内缝洞体发育与构造裂缝发育关系密切,其表层岩溶带内缝洞体发育受构造作用产生的高角度裂缝、网状缝及压溶缝控制。在S80单元经历的4次重要构造变形过程中,加里东中期,海西早、晚期的褶皱和断裂作用对该区裂缝的产生和走向及后期溶蚀作用发育方向具有控制作用。据此,将S80单元内缝洞体发育模式划分为沉积成岩期、构造挤压期、抬升溶蚀期、溶蚀扩大及回流充填期4个阶段。The fractured vuggy unit of S80 is an important fractured zone in the Tahe oilfield, which stretch across the sixth and the seventh area. Methods based on petroleum geology, sedimentology and structural geology were used to study the S80 fractured structure model in detail. Sinkholes, river cave, tributaries cave and peripheral hole were found out. The sinkholes, river Cave, cave branch flow and peripheral holes mainly develop in the epikarst zone. And the sinkholes distribute along the structural low and the slope presenting a string of beads. A few peripheral holes were found out in seepage karst cave zones. River cave is the main part of runoff karst belt which grows parallel or nearly parallel to the direction of formation and superposed in the longitudinal direction. The deep seam andvuggy zone is characteristic of slit strip liking underground rivers, having close relationship with fault. High angle fractures, joints and pressure solution seam mesh were found in S80 unit which are controlled by the tectonization and influence the cracks and caves development in the epikarst. Therefore, limestone caves mainly grow in the surface layer of the karst belt with horizontal distribution. The deep seam cave zone has close relationship with the deeper fracture and exhibits underground river characteristics. In the Akekule and its adjacent areas, there are four important tectonic deformations which lead to the formation fracture development in S80 unit. During middle Caledonian, early and late Hercynian, the folding and faulting controls the crack growth and its direction in this area. Accordingly, the fractured-vuggy model of S80 wells in the fractured karst area was summed up into four stages: sedimentary and diagenesis, tectonic compression, uplift and dissolution, erosion expansion and back filling period, and the controlling factor of different periods on cave formation were proposed.

关 键 词：缝洞体 落水洞 干流洞 表层岩溶带 碳酸盐岩油藏 塔河油田 

分 类 号：TE344[石油与天然气工程—油气田开发工程]