【作者】 常象春；

【导师】 王明镇；

【作者基本信息】 山东科技大学 ， 矿产普查与勘探， 2007， 博士

【摘要】 随着勘探程度的不断加深，剩余油气资源的隐蔽性越来越强，岩性油气藏在勘探领域中显现出越来越重要的地位和作用。临南洼陷作为惠民凹陷最重要的洼陷，经历四十余年的构造油气藏勘探后，寻找岩性油气藏成为下一步勘探的重点。但目前临南洼陷的相关研究中，尚未建立全区的层序地层格架，对控制岩性油气藏形成的沉积体系认识不够明了，尚未搞清层序格架中沉积体系的分布、演化及其对岩性圈闭形成的影响，成藏主控地质因素和岩性油气藏的形成机理需要进一步明确，岩性油气藏在平面与精细层序格架中分布规律不清楚，均制约了有利勘探目标区预测的展开。本文围绕岩性油气藏形成这一主线，寻找有利地区这一目的，利用高分辨率层序地层学，结合区域构造演化，将临南洼陷沙三段划分为1个长期基准面旋回。同时根据在研究区内识别出的8个具有时间意义的界面，将其细分为4个中期基准面旋回，系统地建立了全区的层序地层格架。根据岩性、结构、沉积构造、古生物特征、测井曲线、地震反射、垂向沉积序列分析，认为临南洼陷沙三段中主要发育有三角洲、扇三角洲、滑塌浊积扇、湖泊相等几种沉积相类型，在平面上形成5种沉积体系组合。区内临邑三角洲、基山三角洲、双丰扇三角洲、江家店—瓦屋扇三角洲等在基准面下降期向洼陷中心推进，基准面上升期三角洲前缘砂体在深水区形成滑塌浊积扇或深水浊积扇，控制着各类岩性圈闭的形成。油气成藏机理研究表明，本区连通性砂体、多级多期活动的断层、多个沉积间断和区域不整合面、火成岩体、泥岩中裂隙组合成复杂的油气输导网络，异常高孔隙流体压力是本区油气成藏的重要动力。油气成藏受控于构造环境、沉积相带、各类输导体系及成藏条件的有机配置。指出临南洼陷内湖盆深水区或三角洲前缘斜坡滑塌浊积岩体部位发育各种成因的砂岩透镜体圈闭。在斜坡带或沟槽的两侧，砂岩上倾尖灭并相变为非渗透岩层，可形成岩性上倾尖灭圈闭；若在上倾方向受断层切割和封堵，可形成构造—岩性圈闭。临南洼陷沙三段岩性油气藏主要围绕基山砂岩体、临南三角洲平原相分流河道砂体和前三角洲浊积砂体、江家店扇三角洲前缘砂体、营子街三角洲前缘滑塌浊积砂体、惠民南坡砂砾岩体分布。根据成藏主控因素，在研究区临南洼陷带、夏口断裂带预测出岩性油气藏有利目标20余个。更多还原

【Abstract】 With the process of petroleum exploration, the concealments of residual petroleum resources were more prominent and lithological oil reservoirs were attracted more attention. As the most important subsag in Huimin sag, Linnan subsag will lay strong emphasis on lithological oil reservoirs exploration after about forty years exploration of structural oil reservoirs. But some deficiencies were fronted in the relative researches in this subsag. Such as lack of establishment of sequence framework for the whole area, ambiguity of depositional systems constrained the formation of lithological traps, especially the distributions and evolutions of depositional systems in sequence framework and their implications, unawareness of the key controlling factors and mechanism of lithological oil reservoirs, vagueness of occurrences of lithological oil reservoirs in lateral and vertical, all of which restraint the predictions of potential targets.Focused on the formation and searching of the lithological oil reservoirs, high resolution sequence stratigraphy and sedimentology were used. Incorporated with regional tectonic evolutions, Es₃ in Linnan subsag was believed to be a long base level cycle. According the eight isochronous sequence interfaces, four middle base level cycles were classified and sequence framework of the whole area was established in detail.The analysis of lithologic characteristics, lithologic texture, sedimentary structures, palaeontology, log curves, seismic reflections and vertical sedimentary series of deposits in Es3 indicated that delta, fan delta, fluxoturbidite fan and lake facies were developed in this subsag and formed five depositional systems in space. During the course of base-level rose, Linyi delta, Jishan delta, Shuangfeng fan delta and Jiangjiadian-Wawu fan delta prograded to the subsag center, while during the course of base-level falling sandbodies of delta fronts would yield fluxoturbidite fans or deepwater turbidite fan in deepwater areas, influencing the formation of kinds of lithologic traps. Researches on formation mechanism of petroleum accumulations suggested that complicated carrier networks were made up of connective sanbodies, faults of various levels activated in different stages, multiple hiatus and regional unconformities, igneous rocks and fissures in mudstones. Abnormal high pore fluid pressure was the chief force driving hydrocarbons secondary migration. Lithologic oil reservoirs in Linnan subsag was under the control of tectonic settings, sedimentary facies, carrier systems and matching of formation conditions.Lens-shaped sandbodies were easy to be yielded in the deepwater areas and fluxoturbidites of the delta fronts, while upclined pinch-out traps formed in the flanks of paleogeosyncline or slope areas of subsag. Associated with faults or paleogeomorphology, lithologic or structural-lithologic oil reservoirs can be formed. Occurrences of Lithologic oil reservoirs in Linnan subsag were around the Jishan sandbody, sandbodies in distributary channel of delta plain and turbidite of prodelta in Linnan delta, sandbodies in delta front of Jiangjiadian fan delta, fluxoturbidite in delta front of Yingzijie delta and sand-gravel bodies in south slope of Huimin sag. In terms of tectonic performances, depositional characteristics, distribution rules of sandbodies, formation conditions and present exploration achievements, over twenty potential targets for lithologic oil reservoir were predicted in Linnan subsag.更多还原