火山岩储层储集空间的构成——以松辽盆地为例  

Components of volcanic reservoir space:A case study from the Songliao Basin

作　　者：吴颜雄[1] 王璞珺[1] 吴艳辉[1] 闫林[2] 杨帝[3] 

机构地区：[1]吉林大学地球科学学院 [2]中国石油勘探开发研究院 [3]中国石油大庆油田有限责任公司

出　　处：《天然气工业》2011年第4期28-33,124-125,共6页Natural Gas Industry

基　　金：国家重点基础研究发展规划(973计划)项目"火山岩油气藏形成机制与分布规律"(编号:2009CB19303);"中低丰度天然气藏大面积成藏机理与有效开发的基础研究"(编号:2007CB209507)

摘　　要：火山岩气藏勘探的核心问题是储层预测,而储层预测的关键是看储集空间是否发育。为此,采集了松辽盆地下白垩统营城组野外露头区及钻井区167块代表性样品,通过对岩石薄片和铸体薄片的观察,利用面孔率统计方法和物性数据分析,研究了火山岩储集空间的构成问题,对比了不同岩性岩相的原生孔隙、次生孔隙和裂缝发育情况,并探讨了原生孔隙和次生孔隙的成因。结论认为:①气孔火山熔岩原生孔隙最发育;致密火山熔岩和火山碎屑熔岩的原生孔隙、次生孔隙、裂缝发育比例相近,前者裂缝较发育,后者原生孔隙较发育;火山碎屑岩和沉火山碎屑岩次生孔隙和裂缝发育比例较大。②火山通道相以砾间孔和裂缝为主;爆发相和喷溢相从底部→顶部各亚相,原生孔隙发育比例上升,次生孔隙和构造缝发育比例下降;侵出相以原生收缩缝为主,火山沉积相以次生孔缝为主。③发育气孔构造、石泡构造、气孔杏仁构造、流纹构造、珍珠构造、柱状节理、间粒结构和熔蚀结构的火山岩易形成原生孔缝;构造作用、风化淋滤作用、溶蚀作用和脱玻化作用等后期成岩作用促进了次生孔隙和裂缝的形成。以上认识对火山岩储层内部构成的细化及火山岩气藏的开发有借鉴意义。Reservoir prediction is the core of volcanic gas reservoir exploration and its focus is the prediction of reservoir space development.A total of 167 outcrop and core samples were collected from the Upper Jurassic Yingcheng Formation in the Songliao Basin.Based on the observation of ordinary and cast thin sections and statistics of surface pores and analyses of poroperm characteristics,the components of volcanic reservoir space,the comparison of the primary pores,secondary pores and fissures in samples of different lithologies and lithofacies are compared,and the origins of the primary pores and secondary pores,are discussed respectively.From such discussion,the following conclusions are drawn.First,as for vesicular lava,their primary pores are most highly developed.In contrast,as for dense lava and pyroclastic lava,the proportions of the development of their primary pores,secondary pores and fissures are approximately the same.But the dense lava has relatively well developed fissures,while the pyroclastic lava has relatively well developed primary pores.As for pyroclastic rocks and sedimentary pyroclastic rocks,the development of their secondary pores and fissures are relatively large in proportions.Second,pore space of volcanic conduit is dominated by inter-gravel pores and fissures.As for explosive facies and effusive facies,the proportion of primary pores increases from bottom to top,while the proportions of secondary pores and tectoclases drop.In contrast,the pore space of extrusive facies is dominated by primary condensed shrinkage fissures and that of volcanic sedimentary facies is mainly of secondary pores and fissures.Third,volcanic rocks of different structures,such as vesicular structure,lithophytic structure,vesicular and amygdaloidal structure,rhyotaxitic structure,perlitic structure,columnar joint,intergranular texture,and melting corrosion structure,can easily form primary pores and fissures.The later-stage diagenesis of tectonism,weathering,dissolution,and devitrification enhance the development of

关 键 词：松辽盆地 火山岩 储集层 储集空间 孔隙 裂缝 岩相 成岩作用 

分 类 号：P618.13[天文地球—矿床学]