【作者】 宋永东；

【导师】 戴俊生；

【作者基本信息】 中国石油大学 ， 地质资源与地质工程， 2010， 博士

【摘要】 饶阳凹陷是渤海湾盆地冀中坳陷的一个次级构造单元,自新生代以来经历了伸展断陷形成期、扩展期和消亡期三个主要的构造演化阶段,并表现出早期伸展、晚期走滑的构造特征。由于凹陷经历了多期的构造运动,造成了凹陷内部复杂的断裂系统,形成了多种不同成因的含油构造样式。复杂的地质特征给油田后期的地质研究和生产实践带来一定的困难,因此,在现阶段开展大连片高精度新三维地震资料解释的基础上,重新进行整体地、系统地认识饶阳凹陷古近纪断裂构造特征和演化过程及其对油气成藏的控制作用,对该凹陷进一步的油气勘探具有现实意义。本论文以构造地质学、沉积学和现代油气成藏的理论和方法为指导,在前人研究的基础上,综合应用区域地质资料、三维地震资料、测井资料和油田开发资料对饶阳凹陷中北部古近系构造单元、断裂系统特征、构造演化和成因机制等方面进行了研究,重点分析了凹陷断裂系统类型及构造特征和凹陷构造成因机制。在此基础上分析了凹陷的油气藏形成与分布特征,讨论了构造岩相带与油气分布的关系,明确了构造演化对油气生运聚的作用和影响,结合生产资料进一步指出该凹陷油气勘探的有利方向。研究表明,饶阳凹陷中北部由北向南可划分为北部基底掀斜翘倾区、中部基底断弯区和南部盖层滑脱断褶区,各区具有不同的构造演化特征。凹陷内正断层发育,走向具有以北东、北北东为主,以北西、近东西向为辅的特点,形成网格状断裂体系。这些断裂构成正向滑动断阶、正向翘倾断块等伸展构造样式和花状构造、雁列构造等走滑构造样式。根据凹陷内各主干断裂几何学和运动学构造特征以及断裂构造样式的不同,将其划分为5大断裂系统,即马西断裂系统、任丘断裂系统、河间断裂系统、留路断裂系统和高阳断裂系统。各断裂系统内部有不同的断裂构造特征及其成因机制,控制着各洼槽的沉积充填和油气分布,各系统之间以不同的变换构造相连。这些断裂系统制约着不同构造样式的展布,共同控制了凹陷的形成和演化。通过恢复各期构造运动造成的地层剥蚀厚度,运用平衡剖面技术分析了凹陷构造演化史。各期构造活动强度不同,致使凹陷内各级断层的活动性也存在差异,具有不同的垂向叠加改造和平面迁移规律,利用断层生长指数和落差等参数定量分析了断层的活动性。在此基础上划分了凹陷构造演化阶段。饶阳凹陷中北部构造成因受到多种因素的制约,其中区域构造应力场的变化起着重要作用。研究认为,伸展方向的旋转、张扭作用方式、伸展断层断面的演化和滑脱构造深度是形成凹陷现今构造格局的主要控制因素,并利用构造应力场数值模拟对其进行了验证。饶阳凹陷中北部古近系是油气勘探成熟区,储量增产难度加大。目前勘探重点是构造—岩性油气藏和地层岩性油气藏。论文最后总结了油气成藏特征,分析了油气藏形成的控制因素,指出断裂活动强度和不整合分布在横向和纵向上控制了油气的运聚成藏,同时有利的构造岩相带和沉积体系也对地层岩性油气藏形成有明显的控制作用。结合油田生产资料分析,指出河间和大王庄地区东营组三段、蠡县斜坡沙河街组一段和马西地区南部沙河街组一段为有利勘探区带,并对其进行了油气成藏条件分析。更多还原

【Abstract】 Raoyang sag is a secondary structural unit in Jizhong depression of Bohai bay basin, it has experienced three main stages of tectonic evolution since the Cenozoic, namely the period of formation, the period of expansion and the period of disappearance. The structural features are tensile stretch at early time and shear-slip at late time. Because of the multi-stage tectonic movements of Raoyang sag, it formed the complex fault system and a variety of different oil-bearing structural styles. As a result, difficulties have been brought to geological research and production of oilfield. Therefore, at present, based on interpretation of the new high-precision three-dimensional seismic data, it will has a reality significance for petroleum exploration in the sag to research holistically and systematically characteristics and evolution of faults of Paleogene, to research its control on hydrocarbon accumulation.Taking the theories of structural geology, sedimentology and modern hydrocarbon accumulation as guidance, the author studied tectonic units, characteristics of fault system, tectonic evolution and genetic mechanism, and other aspects for Paleogene of Raoyang sag by using all kinds of data. The research focuses on the analysis of types and structural features of fault systems and genetic mechanism of sag. On this basis, the forming and distributing characteristics of the reservoir was also analyzed, the relationship between the tectonic facies zones and distribution of oil was discussed, and the influence of tectonic evolution on the hydrocarbon migration and accumulation were defined. At last, the further favorable exploration zones were proposed by using the production data.The conclusions have shown that the middle-northern area of Raoyang sag can be divided into three different tectonic regions from north to south: it is tilted basement in northern area, base fault-bend in middle area and detachment fault-fold of cover rock in southern area. The normal faults are main fault in the sag, its strike are mainly NE strike and NNE strike, NW strike and EW strike were secondary. Those faults form grid-like fault systems, and constitutes extensional and strike-slip structural styles, such as forward slip-fault, forward tilted fault block and flower-like structure.According to the different geometry and kinematics features of the main faults, as well as different characteristics of structural styles, the faults in the sag can be divided into five major fault systems, that is, Maxi fault system, Renqiu fault system, Hejian fault system, Liulu fault system and Gaoyang fault system. Within the fault system there are different characteristics and genetic mechanisms, among the various fault systems there are different transfer structures. The fault systems constraints of different structural styles and jointly controls the formation and evolution of Raoyang sag.Through the restoration of erosion thickness caused by the tectonic movement, the author used balanced cross-section to analyze the tectonic evolution. The different phases of tectonic activity have different intensity, which resulted in the different fault activity. The fault activity was analyzed quantitatively by using parameters such as the growth index and fault throws. On this basis, the stages of tectonic evolution of sag were also classified.There are many factors of forming sag. A change of the regional tectonic stress field plays an important role. Researching results suggest that rotation pattern of stretching direction, shear tectonic system, the evolution of extensional faults and depth of decollement structure are the main factors that form the framework of current tectonic. Furthermore, the conclusion was verified by taking advantage of numerical simulation of tectonic stress field.In the last part of thesis, the forming characteristics of petroleum in Raoyang sag were summarized and controlling factors of hydrocarbon accumulation was also analyzed. The author pointed out that activity intensity of fault and unconformity control the oil and gas migration and accumulation. At the same time, beneficial structural facies belts and sedimentary system also have controlling on the stratigraphic-lithologic reservoirs. According to analytical results of production data, one member of Shahejie formation of Lixian Slope and the southern region of Maxi area, three member of Dongying formation of Dawangzhuang-hejian region were taken as the favorable exploration zones.更多还原