川东北地区灯四段储层成岩作用及孔隙演化  

Reservoir diagenesis and porosity evolution of the 4th member of the Dengying Formation in northeastern Sichuan Basin

作　　者：李毕松[1] 金民东 朱祥[1] 代林呈 杨毅[1] LI Bisong;JIN Mindong;ZHU Xiang;DAI Lincheng;YANG Yi(Sinopec Exploration Company,Chengdu 610041,China)

机构地区：[1]中国石化勘探分公司,四川成都610041

出　　处：《地学前缘》2023年第6期32-44,共13页Earth Science Frontiers

基　　金：国家自然科学基金企业创新发展联合基金项目“海相深层油气富集机理与关键工程技术基础研究(U19B6003)”。

摘　　要：本文以四川盆地川东北地区灯四段储层为研究对象,基于区内丰富的野外露头和钻井取心资料,结合扫描电镜、阴极发光和地化分析等测试手段,对灯四段储层成岩作用、成岩演化序列和储层孔隙演化进行了详细研究。结果表明:灯四段碳酸盐岩储层在沉积作用和成岩作用过程中广泛地受到孔隙流体和成岩变化的影响,依序经历海底胶结作用、同生-准同生大气淡水溶蚀作用、早成岩期相控岩溶作用、浅埋藏期胶结充填作用、中-深埋藏期溶蚀作用、重结晶作用和构造破裂作用等。其中,由于复杂的成岩流体影响,主要的胶结充填作用表现为五期白云石充填和两期与火山-热液活动相关的硅质充填,对储层破坏最为严重。而早成岩期相控岩溶作用则是灯四段储层形成的最关键建设性成岩作用,与典型表生岩溶作用表现出明显的差别。川东北地区灯四段储层在这些成岩作用的动态叠加中,最终形成现今的储集面貌。研究结果可为寻找区域优质储层提供更科学的地质依据。Based on abundant field outcrop and core data,combined with scanning electron microscopy,cathodofluerescence microscopy and geochemical analysis,carbonate diagenesis,diagenetic sequence and pore evolution in the 4th member of the Dengying Formation in northeastern Sichuan Basin were studied in detail.Widely influenced by pore fluid and diagenetic changes during sedimentation and diagenesis,the carbonate reservoir underwent submarine cementation,syngenetic-parasyngenetic atmospheric freshwater dissolution,karstification controlled by sedimentary facies in the eogenetic stage,cement filling under shallow burial,dissolution under mid-deep burial,recrystallization and tectonic rupturing.Due to complex diagenetic fluids,the main cement fillings featured five periods of dolomite cements and two periods of siliceous cements related to volcano-hydrothermal activity,and the damage to the reservoir was most serious.However,facies-controlled eogenetic karstification was obviously different from typical epigenic karstification,and was the most critical,constructive diagenesis impacting the reservoir development in the study area.And dynamic superposition of different diagenesis eventually resulted in the current reservoir features.Results from this study provided a geological basis for the discovery of high-quality reservoirs in the region.

关 键 词：成岩作用 成岩序列和孔隙演化 相控岩溶 灯四段 川东北地区 

分 类 号：P588.2[天文地球—岩石学] P618.13[天文地球—地质学]