成都理工大学学报（自然科学版）2025，Vol.52Issue(4)：631-642,12.DOI:10.12474/cdlgzrkx.2024061302
川西须家河组二段深层致密砂岩储层伊利石晶间孔成因
The genesis of illite intercrystalline pores in the deep-layer tight sandstone reservoirs of the second member of the Xujiahe Formation in western Sichuan Basin
摘要
Abstract
Micropores in deep clastic rock reservoirs play an important role in the storage and migration of natural gas,among which illite intercrystalline pores are a very important type.To determine the effect of illite intercrystalline pores on the physical properties of clastic rock reservoirs and the effectiveness of natural gas migration and storage,the deep tight sandstone reservoir of the second member of the Xujiahe Formation in the western depression of Sichuan Basin is studied.In our comprehensive analysis method we use thin slice observations,X-ray diffraction,argon ion polish,and scanning electron microscopy.The characteristics and formation process of illite intercrystalline pores in deep clastic rock reservoirs and the influence of micropores on reservoir physical properties are analyzed.The results show that the pores of the second member of the Xujiahe Formation are filled with network or dense illite,containing micropores and nanopores with diameters ranging from 1.4×102 nm to 553.4×102 nm.In the process of diagenetic evolution,kaolinite formed by early feldspar dissolution,which filled in the primary intergranular pores,inhibiting deep compaction and preserving the intergranular volume.With an increase of ground temperature,kaolinite underwent further illitization,and the volumes of the clay mineral intercrystalline pores increased.The diameters of these intercrystalline pores are much larger than the size of methane molecules,which allowed them to undergo Darcy seepage.Therefore,illite intercrystalline pores are an important and effective storage space in deep natural gas reservoirs.关键词
伊利石晶间孔/黏土矿物/成岩作用/须家河组/川西坳陷Key words
illite intercrystalline pores/clay minerals/diagenesis/Xujiahe Formation/western Sichuan depression分类
天文与地球科学引用本文复制引用
CUI Rong,YANG Tian,CAI Laixing,LI Zheng,LIU Feiyang..川西须家河组二段深层致密砂岩储层伊利石晶间孔成因[J].成都理工大学学报（自然科学版）,2025,52(4):631-642,12.基金项目
国家社会科学基金重大项目(24&ZD164). （24&ZD164）
