Shaximiao gas reservoirs in Gaomiao block are low porosity and permeability tight reservoirs with a depth of 2,300 m to 3,100 m,an average porosity of 8.24%,and an average permeability of 0.22 ×10 -3 μm2 .Due to the reservoir damages caused by strong stress -sensitive,sand production and gas condensate,there are rapid drop of wellhead pressure, low flowback rate,and the fast production decline during flowback after fracturing.Aiming at the problems,it was proposed out that optimizing the fracturing fluid and proppant combination,and pressure control during flowback.The optimized frac-turing fluid consists of a 0.1% of the demulsifier,the anti -swelling agent composition,0.5%WD -5 +0.5%BM-B10+1%KCl,and the proppant combination with 80% of 30 /50 mesh +20% of 40 /70 mesh ceramisites.And the pressure is controlled to be more than 15MPa.Finally,it was formed that the fracturing technology suitable for the Shaximiao reservoir. The field applications in 18 wells have achieved good results,with the average single well test production increased by 129%.%GM区块沙溪庙组气藏埋深2300～3100 m，平均孔隙度8.24％，渗透率0.22×10－3μm2，为低孔低渗致密储层。该类储层压后排液过程中井口压力下降快，返排率低，产量下降快，主要原因是储层的强应力敏感性、地层出砂及凝析油对储层的伤害。针对以上问题，提出了优化压裂液配方和支撑剂组合及控压排液对策。优化的压裂液中破乳剂加量为0.1％，防膨剂加量组合为0.5％WD －5＋0.5％BM－B10＋1％KCl，支撑剂采用80％的30／50目＋20％的40／70目陶粒组合，排液压力控制在15 MPa 以上。最终形成了适用于 GM沙溪庙凝析油气藏的压裂技术，现场应用18口井均取得较好效果，较前期平均单井测试产量提高129％。
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