川西简阳地区二叠纪火山岩成岩作用及其对储集性能的影响  

Diagenesis of Permian volcanic rocks and its influence onreservoir performance in Jianyang area,Sichuan,China

作　　者：罗冰[1] 马羚 刘冉 杨帅[2] 李亚 李乾 周刚[1] 王尉 LUO Bing;MA Ling;LIU Ran;YANG Shuai;LI Ya;LI Qian;ZHOU Gang;WANG Wei(Research Institute of Petroleum Exploration and Development,PetroChina Southwest Oil and Gas Field Company,Chengdu 610041,China;Institute of Sedimentary Geology,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]中国石油西南油气田分公司勘探开发研究院,成都610041 [2]成都理工大学沉积地质研究院,成都610059

出　　处：《成都理工大学学报（自然科学版）》2020年第6期711-723,共13页Journal of Chengdu University of Technology: Science & Technology Edition

基　　金：中国石油天然气股份有限公司重大科技专项(2016E-0604);中国石油天然气股份有限公司科技项目(kt2017-01-01-01-1)。

摘　　要：利用岩心观察、薄片鉴定、地球化学测试、扫描电镜等方法,研究川西简阳地区二叠纪火山岩的成岩作用类型及演化特征,并分析成岩作用对储层储集性能的影响。研究区内火山岩储层的储集空间组合为粒间孔、脱玻化孔和溶蚀孔,其发育受11类成岩作用影响,成岩演化经历了冷却固结成岩、岩浆期后热液作用、风化淋滤和埋藏成岩4个阶段。计算结果显示,脱玻化作用为火山岩最大增加15.1 cm 3/kg的储集空间,最大增孔体积达4%。钠长石溶蚀可增加1.19%~2.39%的储集空间。火山岩岩性相同时,风化程度越高,物性越好。黏土矿物绿泥石化后的体积大于蚀变前的体积,证明绿泥石化会降低储集空间。研究区内火山岩储集空间的形成主要受控于脱玻化作用、风化淋滤作用和溶蚀作用,而绿泥石化和充填胶结作用是主要的减孔因素。By means of drilling core observation,thin section identification,geochemical test and scanning electron microscope analysis,the diagenetic types and evolution characteristics of Permian volcanic rocks in Jianyang area of western Sichuan are studied,and the influence of diagenesis on reservoir performance is analyzed.The reservoir space assemblages of volcanic rocks in the study area are composed of intergranular pore,de-vitrified pore and dissolution pore,and their development is related to and affected by 11 types of diagenesis.Diagenesis in Permian volcanic rocks in Jianyang area has undergone such stages as cooling consolidation diagenesis,post-magmatic hydrothermal action,weathering leaching and burial diagenesis.The calculation results show that de-vitrification increases the reservoir space of the volcanic rocks by 15.1 cm 3/kg at most and increases the pore volume by 4%at most,and the storage space of sodium feldspar increased by 1.19%~2.39%.It shows that the higher the degree of weathering,the better the physical properties.The volume of clay minerals after chloritization has more than doubled compared with that before alteration,which proves that chloritization reduced the storage space.It is recognized that the formation of volcanic reservoir space in the study area is mainly controlled by deglazing,weathering and leaching and dissolution,while chloritization and filling cementation are the main factors causing pore reduction.

关 键 词：川西地区 二叠纪 火山岩 成岩作用 储集性能 

分 类 号：P588.211[天文地球—岩石学] TE122.21[天文地球—地质学]