塔河油田奥陶系碳酸盐岩基质孔缝型储集体特征  

Ordovician carbonate rock matrix fractured-porous reservoirs in Tahe Oilfield

作　　者：毛毳[1,2] 钟建华[1,3] 李勇[1] 王有智[2] 牛永斌[4] 倪良田[1] 邵珠福[5] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院 [2]中国石油大庆油田勘探开发研究院 [3]中国科学院广州地球化学研究所 [4]河南理工大学资源环境学院 [5]国土资源部海洋油气资源与环境地质重点实验室

出　　处：《石油勘探与开发》2014年第6期681-689,共9页Petroleum Exploration and Development

基　　金：国家重点基础研究发展计划(973)项目(2011CB101001);国家科技重大专项(2011ZX05014-002-002)

摘　　要：采用岩心观察、薄片鉴定、阴极发光、显微荧光、扫描电镜与能谱分析等多种技术方法,研究塔河油田云斑灰岩基质孔缝型油藏储集体特征。塔河油田云斑灰岩的白云石砂屑团块中赋存大量石油,在中下奥陶统一间房组和鹰山组广泛分布,厚度大,目前开发的油气有相当一部分来自于这种灰岩基质,而不是以往认识的完全来自于缝洞系统。白云石砂屑团块岩心上表现为不规则斑状或绸带状分布,在许多层段约占岩心总比表面积的40%,砂屑部分总孔隙面孔率也达39%左右。砂屑部分为结晶较好的白云石,白云石晶体直径主要集中在100-350μm,相当于中细砂级;高压压汞测试结果显示砂屑团块储集物性较泥晶灰岩优越很多,孔隙度为12.57%-36.39%。砂屑团块周围缝合线和微裂隙极为发育,密集的缝合线和微裂隙连通了白云石砂屑团块含油单元,使微孔、微缝中的石油能够连通起来,成为有效的储集空间。Features of porphyritic limestone matrix fracture-vug reservoirs in Tahe Oilfield was examined by core observation, thin section identification, cathodoluminescence, microscopic fluorescence, scanning electron microscope and energy spectrum analysis. Thick and widespread in the Lower-Middle Ordovician Yijianfang and Yingshan Formations, sand-clastic masses in the porphyritic limestone are rich in oil, quite a proportion of oil and gas produced currently is from their matrix rather than completely from the fracture cave system in the past understanding. In irregular spot or ribbon shape on cores, dolomitic sand-clastic masses usually account for about 40% of the total surface of core in many layers, arenite section has a surface porosity of around 39%. The arenite section is well-crystallized dolomite, the dolomite crystals are mainly 100-350 μm in diameter, equivalent to medium-fine sand; high-pressure mercury injection experiment results show that the reservoir physical property of sand-clastic masses is much better than that of micrite limestone, with a porosity of 12.57%-36.39%. There developed abundant stylolites and microcracks around the sand-clastic masses, which connect the oil bearing units of dolomitc sand-clastic masses, making micropores and microcracks communicate and become effective reservoir space.

关 键 词：碳酸盐岩 基质孔缝型储集体 云斑灰岩 砂屑团块 塔河油田 奥陶系 

分 类 号：TE122.2[石油与天然气工程—油气勘探]