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平落坝气田须二段是该气田的主要产气层段，产层埋深３ ４００ ～３ ９００ ｍ ，以细粒、细—中粒或中粒长石石英砂岩和长石岩屑砂岩组成的裂缝—孔隙型致密储层。粘土矿物含量为５％ ～１５％ ，其中伊利石占８８ ％ ～９４ ％ ，绿泥石为５ ％ ～１０ ％ ，多数样品中还发现了数量不等的伊蒙混层矿物。储层平均孔隙度为３．５５ ％ ，渗透率为０．２ ×１０－ ３μｍ２ ，平均水饱和度为５４％ 。气藏各井投产初期均产出泥浆水，生产极不稳定，一般都需要解堵后投产，其产气量可提高３ 倍以上。通过实验证实，钻井液对该气田须二段气藏存在伤害，渗透率平均伤害率为５０ ％ ，其损害的机理一是钻井液滤液进入地层增大了水膜厚度，二是钻井液微粒侵入岩心堵塞了渗流通道而造成。为了减轻损害，建议改进钻井液密度，在平衡压力或略高于地层压力条件下钻开产层。
The second member of Pingluoba gas field is the main gas-bearing interval in this gas field. The pay zone is 3 400-3 900 m deep and consists of fine-grained, fine-medium-sized or medium-grained feldspar quartz sandstone and feldspar lithic sandstone Crack-pore tight reservoirs. Clay minerals range from 5% to 15%, of which illite accounts for 88% to 94% and chlorite ranges from 5% to 10%. The average porosity of the reservoir is 3.55%, the permeability is 0.2 × 10-3μm2, and the average water saturation is 54%. In the early stage of gas wells production, all wells produce muddy water and the production is extremely unstable. Generally, all wells need to be unblocked and put into operation, and their gas production can be increased by more than 3 times. It is confirmed through experiments that the drilling fluid has damage to the gas reservoir of the Second Member of the Xuerdian Gas Field and the average damage rate of the permeability is 50%. The mechanism of the damage is that the drilling fluid filtrate enters the formation to increase the water film thickness and the second is that the drilling fluid particles invade The core blocks the seepage channel. To mitigate the damage, it is advisable to improve the drilling fluid density and drill the pay zone at or slightly above the formation pressure.