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为了揭示川西致密砂岩气层保护技术实施的工程地质条件，研究了川西致密砂岩气藏的工程地质特点：（１）发育多套气层，砂层厚度和规模差异显著；（２）地层压力剖面为超高压异常，呈现多个压力系统；（３）储层由浅部的近常规渐变为致密、超致密类型，基块毛管压力急剧升高；（４）裂缝发育非均质，微裂缝提供了致密砂岩储层的主要渗透性；（５）粘土矿物类型丰富，储层表现为强烈的水敏和碱敏性；（６）储层渗透率对应力变化异常敏感。致密砂岩气藏的工程地质特点决定了其损害机理显著地不同于常规油气层，保护技术措施更应强调针对性。分析表明，应用水平井技术、气体类工作流体或屏蔽式暂堵技术对裂缝性致密砂岩气层保护较理想。
In order to reveal the engineering geological conditions for the implementation of tight sandstone gas reservoirs in western Sichuan, the engineering geological features of tight sandstone gas reservoirs in western Sichuan are studied: (1) multiple sets of gas layers are developed, with significant differences in thickness and scale; (2) For the UHP anomaly, a number of pressure systems are presented. (3) The reservoir gradually changes from a shallow conventional shallow to a tight and ultra-dense type, and the capillary pressure of the base plate increases sharply. (4) Inhomogeneous fracture development provides micro-cracks The main permeability of tight sandstone reservoirs; (5) the abundant clay minerals, the reservoir shows strong water and alkali sensitivity; (6) the permeability of reservoir is sensitive to the change of stress. The engineering geological characteristics of tight sandstone gas reservoirs determine that the damage mechanism is significantly different from that of conventional oil and gas reservoirs, and the protection measures should be more targeted. The analysis shows that the application of horizontal well technology, gas type working fluid or shielded temporary plugging technology is more suitable for the protection of fractured sandstone gas reservoirs.