四川盆地大湾-毛坝-铁山坡地区飞仙关组储层特征及其主控因素  

Reservoir rock characteristics and main controlling factors of the Feixianguan Formation in the Maoba-Dawan-Tieshanpo area, Sichuan basin

作　　者：何莹[1] 胡东风[2] 张箭[1] 黎平[1,3] 盘昌林[4] 王岩[1] 刘大成[1] 

机构地区：[1]中国石化西南油气分公司勘探开发研究院,四川成都610081 [2]中国石化勘探南方分公司勘探处,四川成都610041 [3]成都理工大学能源学院,四川成都610059 [4]中国石化勘探南方分公司川东北勘探前线指挥部,四川达州635000

出　　处：《中国地质》2008年第5期922-939,共18页Geology in China

基　　金：国家重点基础研究发展计划项目(2006CB202304);中石化重点攻关项目(PK0758)联合资助

摘　　要：21世纪是中国海相碳酸盐岩油气勘探开发的一个大发展期,目前中国海相碳酸盐岩油气田多数为埋深达4000m以下的深部古生界层系。如何在深层碳酸盐岩地层中寻找优质储层已成为油气勘探家们关心的焦点;近期发现的普光气田是中国目前发现的碳酸盐岩储层次生孔隙最为发育的气藏,并严格受控于沉积微相的分布及白云岩化、埋藏溶蚀作用等成岩相的控制。本文以"相控论"理论为指导,对川东北普光外围大湾—毛坝—铁山坡地区下三叠统飞仙关组优质储层形成与演化起主控作用的"储集相"——有利的沉积相、成岩相进行详细研究和解剖。通过露头剖面、钻井、测井和地震等资料的研究,结合单因素分析、多因素综合作图法,认为大湾—毛坝—铁山坡地区飞仙关组主要发育斜坡、台缘浅滩、开阔台地和局限台地4个沉积相单位。结合岩心详描和室内大量岩心、岩屑薄片以及铸体薄片的观察和研究,认为控制储层形成的关键是白云岩化、埋藏溶蚀作用等成岩相。根据铸体薄片鉴定、扫描电镜分析、物性分析及压汞分析等手段,研究认为优质储层以大套溶孔粉-细晶残余鲕粒白云岩为特征,岩石中溶孔极为发育,以大孔粗喉型、中孔中喉型为主;物性较好,以高孔高渗和中孔中渗为主,孔渗相关性明显。相控储层作用明显,纵向上主要分布于飞二段至飞一段顶部,横向上台缘浅滩为有利储层的分布区。台缘浅滩相带控制了本区优质储层的岩性及大致空间分布范围,白云岩化及埋藏溶蚀作用则决定了优质储层的最终分布范围和储集性能。通过对大湾—毛坝—铁山坡地区台地边缘浅滩储层"相控论"的探讨,以期对中国深层海相碳酸盐岩的勘探起到抛砖引玉的作用。The 21st century is a great development period of China＇s oil and gas exploration and development of marine carbonate rocks. For the moment, the majority of China＇s marine carbonate oil and gas fields are buried below 4000 m depth in the Paleozoic sequence. How to look for favorable reservoirs in deep carbonate rocks has become the focus of attention of petroleum geologists. The Puguang gas field discovered recently is a gas accumulation with the best developed secondary pores among carbonate reservoirs discovered in China at present and is strictly controlled by the distribution of sedimentary facies, dolomitization and buried dissolution. In this paper, a detailed study and anatomy of the ＂reservoir facies＂-favorable sedimentary facies and diagenetic facies-is conducted under the guidance of the ＂facies control theory＂, which controls the formation and evolution of the reservoir of the Lower Triassic Feixianguan Formation in the Dawan - Maoba - Tieshanpo area in the surroundings of Puguang. According to the outcrop section, drilling, logging and seismic data, combined with the ＂single-factor analysis and muhifactor comprehensive mapping method＂, four sedimentary units are proved to be developed in the Feixianguan Formation in the Dawan - Maoba - Tieshanpo area; they are platform slope, platform shoal, open platform and restricted platform. Based on the detailed description of cores and indoor observations and studies of large numbers of core and cutting thin sections and casting slices, the authors think that the key factors which control the reservoir formation are dolomitization, buried dissolution, and so on. According to casting slice identification, scanning electron microscopy, analysis of mercury and other means of analysis, it is found that the favorable reservoir is characterized by large sets of porous finely and very finely crystalline residual oolitic dolostone. Solution pores in rocks are very well developed, consisting dominantly of the large pore and coarse throat type, medium por

关 键 词：深层碳酸盐岩 相控论 储集相 台缘浅滩相 成岩相 优质储层 飞仙关组 四川盆地 

分 类 号：P618.13[天文地球—矿床学]