义和庄凸起东区前第三系顶部风化壳结构发育模式及对油气运聚的影响  

Structure Model of Weathered Crust on the Top of Pre-Tertiary and Its Influence on Petroleum Migration and Accumulation in East Part of Yihezhuang Uplift

作　　者：赵乐强[1] 张金亮[1] 宋国奇[2] 隋风贵[2] 王学军[2] 向立宏[2] 卓勤功 

机构地区：[1]中国海洋大学海洋地球科学学院,山东青岛266100 [2]中国石油化工股份有限公司胜利油田分公司地质科学研究院,山东东营257015

出　　处：《沉积学报》2008年第3期435-444,共10页Acta Sedimentologica Sinica

基　　金：中国石油化工股份有限公司重大科技攻关课题“济阳坳陷第三系不整合油气藏形成与分布规律”(P06012)资助

摘　　要：基于地质综合研究,系统分析了济阳坳陷义和庄凸起东部地区前第三系顶部风化壳结构特征,深入剖析了其形成主控因素,建立了该区风化壳结构发育模式,并探讨了风化壳结构对油气运聚的影响。研究认为,义和庄凸起东区前第三系顶部风化壳中,风化粘土层厚度薄,分布地区局限,物性差;半风化岩石全区发育,岩石类型多样,除部分半风化碳酸盐岩顶部存在一层致密"硬壳"外,物性多得到明显改善。风化壳结构形成受控于岩相、气候、时间、古地形、构造、后期保存程度等6大因素;多种因素相互耦合,决定了风化壳结构的空间发育;风化粘土层、半风化岩石顶部"硬壳"对油气起遮挡、封盖作用,顶部无"硬壳"的半风化岩石则可大大提高前第三系岩层的储集性能和不同层系之间的横向连通性。Based on integrated study, the paper analyzed characteristics of the structure of weathered crust on the top of Pre-Tertiary in the east part of Yihezhuang uplift of Jiyang depression. Key factors controlling its formation were anatomized, structure model of weathered crust was established, and its influence on petroleum migration and accumulation was discussed. Results show that weathered clay layer in the studied weathered crust is thin with limited distribution, and reservoir property is poor; while semi-weathered rock of various lithologies extensively developed in the whole area, except for the tight ＂hard crust＂ on the top of semi-weathered carbonate stone, reservoir property was improved obviously. Structure of weathered crust was controlled by lithofacies, paleoclimate, weathering time, paleotopography, tectonic structure, and later stage preservation. Reciprocal coupling of these factors determines spatial distribution of the structure of weathered crust. The weathered clay layer and ＂hard crust＂ on the top of semi-weathered rock serves as caprock for petroleum reservoir, while semi-weathered rock without ＂hard crust＂ can improve reservoir property of Tertiary system and serve as lateral migration path between different strata.

关 键 词：前第三系 风化壳结构 发育模式 油气运聚 义和庄凸起 

分 类 号：P512.2[天文地球—地质学] TE122.1[石油与天然气工程—油气勘探]