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为了阐明致密含气砂岩储层的损害机理，进而为制订保护气层技术措施提供依据，研究了川西典型气田侏罗系—上三叠统致密砂岩储层中的粘土矿物，采用薄片、ＸＲＤ、ＳＥＭ方法分析了粘土矿物含量、类型、产状和微结构，并讨论了纵向演变规律。研究指出粘土矿物含量随深度增加而降低；粘土类型为高岭石、绿泥石、伊利石、蒙皂石、绿／蒙间层和伊／蒙间层；主要演化路径有蒙皂石→绿／蒙间层→绿泥石、蒙皂石→伊／蒙间层→伊利石、高岭石→伊利石。常见七种粘土微结构类型，随埋深增加微结构稳定性提高。研究还表明粘土自身的敏感性及因粘土的存在而形成的储层致密性是储层易被损害的根本原因，防止致密储层损害，首要工作是有效地解决粘土矿物问题。但仅就防止粘土损害而言，气体类工作流体具有一定程度的优越性。
In order to clarify the damage mechanism of tight gasbearing sandstone reservoirs and to provide the basis for developing technical measures for gas reservoirs, the clay minerals in the JurassicTypetupock tight sandstone reservoirs in a typical gas field in western Sichuan were studied. SEM analysis of clay mineral content, type, occurrence and microstructure, and discusses the vertical evolution. The study shows that the content of clay minerals decreases with the increase of depth; the clay types are kaolinite, chlorite, illite, smectite, green / monolayer and i / monolayer; the main evolution path is smectite → green / Interlayer → chlorite, smectite → Iraq / mask → illite, kaolinite → illite. Common seven types of clay microstructure, with the increase of the depth of the micro-structure to improve stability. The study also shows that the sensitivity of clay and the tightness of the reservoir due to the existence of clay are the basic causes of the easily damaged reservoirs. Preventing the damage of tight reservoirs, the primary task is to effectively solve the problem of clay minerals. However, gas-based working fluids have a degree of superiority only in terms of preventing clay damage.