渤海莱州湾凹陷南斜坡中生界火山岩储层特征和控制因素  

Characteristics and Controlling Factors of Mesozoic Volcanic Rock Reservoir in Southern Slope of Laizhou Bay Depression,Bohai Bay Basin

作　　者：任梦怡 范洪军 陆国超 柏佳伟 唐华风[2] Ren Mengyi;Fan Hongjun;Lu Guochao;Bai Jiawei;Tang Huafeng(CNOOC Research Institute Co.,Ltd.,Beijing 100028,China;College of Earth Sciences,Jilin University,Changchun 130061,China)

机构地区：[1]中海油研究总院有限责任公司,北京100028 [2]吉林大学地球科学学院,长春130061

出　　处：《吉林大学学报(地球科学版)》2025年第1期15-30,共16页Journal of Jilin University:Earth Science Edition

基　　金：国家自然科学基金项目(41790453);国家科技重大专项(2016ZX05026-004-001)。

摘　　要：基于岩心和铸体薄片,采用镜下鉴定、扫描电镜分析、孔渗测试、恒速压汞测试、图像分析、埋藏史分析等方法,开展渤海莱州湾凹陷南斜坡垦利16构造中生界火山岩储层特征、主控因素和储层演化研究。结果表明:识别出7类16型储集空间,储层类型为裂缝-孔隙型,具有大孔径、中—粗喉的特征,属于优质火山岩储层;储层受岩性岩相、溶蚀作用和构造作用控制,与埋深关系不明显;储层物性由好到差的顺序为凝灰岩、火山角砾岩、火山集块岩、角砾熔岩、沉火山角砾岩、凝灰熔岩、安山岩和英安岩。流体对长石斑晶和基质的溶蚀溶解作用形成的孔隙贡献较大,表明埋藏前风化和埋藏流体溶蚀阶段是储层形成的重要时期;杏仁体内孔、粒间孔、炸裂缝、宏观和微观龟裂缝、隐爆缝形成于喷发同期,对孔隙贡献率有限。火山碎屑熔岩和熔岩的构造裂缝主要形成于埋藏前阶段白垩纪郯庐断裂带左行走滑应力场和沙河街期的拉张环境,火山碎屑岩的构造裂缝主要形成于埋藏后阶段的郯庐断裂带右行走滑应力场和沙河街期的拉张环境。综上可知,在埋藏浅的地区经受强构造改造和风化作用的火山碎屑岩是勘探的有利目标。Based on core and cast thin section data,the reservoir characteristics,reservoir controlling factors,and reservoir evolution of Mesozoic volcanic rocks in block Kenli-16 were studied by means of microscopic identification,scanning electron microscopy,porosity and permeability testing,constant velocity mercury injection,image analysis and burial history analysis.Seven types of 16 reservoir spaces are identified in block Kenli-16.The reservoir type is pore-fracture type.It is characterized by large pore size and medium-big throat,and belongs to high-quality volcanic rock reservoir.The reservoir is controlled by lithology,dissolution diagenesis,and tectonism and has no obvious relationship with burial depth.The descending order of reservoir quality is tuff,lapilli,volcanic breccia,welded breccia,reworked volcaniclastics,ignimbrite,andesite,and dacite.The fluid contributes greatly to the porosity formed by the dissolution of feldspar porphyry and matrix,the results show that pre-burial weathering and burial fluid dissolution are important stages of reservoir formation.The amygdaloid,intergranular pores,explosive cracks,macroscopic and microscopic cooling fractures,and crypto-explosive fractures were generated during syn-eruption stage,and their contribution rate to pores was limited.The tectonic fractures of pyroclastic lava and lava are mainly formed in the pre-burial stage,the left-lateral strike-slip stress field of Tanlu fault zone in Cretaceous period and the extensional environment of Shahejie stage.The tectonic fractures of pyroclastic rocks are mainly formed in the post-burial stage,the right-lateral strike-slip stress field of Tanlu fault zone in Cretaceous period and the extensional environment of Shahejie stage.In conclusion,pyroclastic rocks that are subjected to strong structural transformation and weathering in shallow buried areas are favorable targets for exploration.

关 键 词：火山岩储层 主控因素 流体 孔隙演化 中生界 莱州湾凹陷 渤海湾盆地 

分 类 号：P618.13[天文地球—矿床学] P588.14[天文地球—地质学]