The matrix petrophysical property of Xu-2 gas reservoir in Pingluoba Field is bad but its fractures are developed,so it is a fracture porosity tight sand reservoir,being of an organically matching of secondary solution pores with developed fractures.Through studying the content,type and occurrence of clay minerals in sandstone,it is shown that the watersensitive and water-locking effects are the major factors of causing potential reservoir damage.The type and degree of reservoir sensitive damage and its relevant games and suggests were researched by use of many core experimental methods.It is considered that in reservoir,the gas logging velocity sensitivity is weak～medium-weak,the degree of its damage being 16.2％～39.9％;and the water-sensitive and water-locking effects are strong,the degree of their damage being 80％～96％，therefore the underbalance drilling technique should be adopted and the entrance of the water,especially the low-mineralized water (＜2 500 mg/L) used for various operations,into formation should be strictly controlled.Because of strong stress sensitivity,when formation pressure increases to 48.3 MPa,porosity loss is 15％～50％,permeability loss is up to 87％～94％ and the permeability is difficult to be restored after confined pressure elimination.Therefore,in the process of gas reservoir development,the producing pressure drop should be strictly controlled to avoid the premature closing of the microfissures and small throats in reservoir owing to rapid decrease in formation pressure.%平落坝须二段气藏储层基质物性差、裂缝发育，系次生溶蚀孔和发育的裂缝有机配置的裂缝—孔隙型致密砂岩体储层。文章从砂岩粘土矿物含量、类型及赋存方式，阐明了水敏、水锁效应是储层潜在伤害的主导因素。以多项岩心实验方法，研究了储层敏感性伤害类型、程度及相应的对策、建议，认为：储层气测速敏属弱—弱偏中，其伤害程度为16.2%～39.9%；水敏、水锁效应强，伤害程度达80%～96%，应采用欠平衡钻井技术及严格控制各种作业过程中水、特别是低矿化度水（小于25 000 mg/L）进入地层；应力敏感性强，当压力升至48.3 MPa时，孔隙度损失为15%～50%，渗透率损失高达87%～94%，且围压撤消后渗透率很难恢复，因此气藏开发过程中，应注意生产压差的控制，避免因地层压力下降太快而导致微裂缝和小喉道的过早关闭。
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