南华北盆地亳州凸起寒武系碳酸盐岩储层特征及主控因素  

Characteristics and main influential factors of the Cambrian carbonate reservoirs in Bozhou Uplift, southern North China Basin

作　　者：魏思宇 周志 李世臻 石砥石 徐秋晨 Wei Siyu;Zhou Zhi;Li Shizhen;Shi Dishi;Xu Qiuchen(Oil and Gas Survey,China Geological Survey,Beijing 100083,China)

机构地区：[1]中国地质调查局油气资源调查中心,北京市100083

出　　处：《天然气勘探与开发》2022年第4期10-19,共10页Natural Gas Exploration and Development

摘　　要：寒武系是南华北盆地深层油气勘探的重要层系,对其碳酸盐岩储层特征与主控因素的认识尚不清楚,阻碍了该地区油气勘探工作。为此,基于野外露头调查、钻井岩心观察和镜下薄片鉴定,对该盆地亳州凸起寒武系海相碳酸盐岩储层的特征和主控因素开展综合分析。研究结果表明:(1)亳州地区寒武系碳酸盐岩主要发育风化壳岩溶型和裂缝型两类储层,前者分布于中寒武统张夏组,后者分布于下寒武统猴家山组和馒头组。(2)本区寒武系碳酸盐岩储集空间类型丰富,孔、洞、缝均有一定程度发育,不同储层的储集空间类型差异明显。风化壳岩溶型储层储集空间以溶蚀孔缝为主,裂缝型储层储集空间以纹层、缝合线为主。区内中—下寒武统发育北北西向和近东西向两期构造裂缝,进一步改善了碳酸盐岩储集性能。(3)寒武系储层发育主要受控于古隆起表生岩溶作用、多期次构造破裂作用和岩石类型等因素。(4)与邻区鄂尔多斯盆地相比,亳州地区寒武系风化壳岩溶储层发育厚度更大,推测与其更长时间暴露地表以及多期次构造破裂作用有关。研究成果对南华北盆地深层油气勘探具有一定借鉴意义。The Cambrian is an important sequence for the exploration of deep oil and gas in southern North China Basin. Nevertheless,both characteristics and main influential factors of the Cambrian carbonate reservoirs remain unclear to hinder an exploration in this area. Thus, based on outcrop survey, core observation and microscopic identification on thin section, a comprehensive analysis on both characteristics and influential factors was conducted for the Cambrian marine carbonate reservoirs in Bozhou Uplift of the basin.Results show that(1) there dominantly developed two reservoir types in the Cambrian carbonate rocks in Bozhou area, namely weathering crust karst and fractured reservoirs, with the former represented by the Middle Cambrian Zhangxia Formation and the latter by the Lower Cambrian Houjiashan and Mantou Formations, respectively;(2) these rocks feature numerous sorts of storage space, all extended with pores, caves and fractures to some extent, whose corresponding reservoirs differ obviously. The storage space in weathering crust karst reservoirs is dominated by dissolution pores and fractures, while that in fractured ones by laminae and stylolite. Two phases of tectonic fractures in NW and near NW strikes stretched in the Lower to Middle Cambrian may further improve the storage capacity for the carbonate reservoirs;(3) the development of Cambrian reservoirs is mainly controlled by epigenic karstification of the paleo-uplift, multi-stage tectonic fracturing, and rock types;and(4) compared with the adjacent Ordos Basin, the Cambrian weathering crust karst reservoirs in Bozhou area are thicker, which are presumed to have something with their exposure to the surface or multiple fracturing for a long time. These results are of certain reference significance for the deep oil and gas exploration in southern North China Basin.

关 键 词：南华北盆地 亳州凸起 寒武系 碳酸盐岩 储层类型 储层特征 

分 类 号：P618.13[天文地球—矿床学]