川中沙溪庙致密油藏为特低孔、低渗致密储层，压裂工艺要求先以滑溜水大排量泵注方式在地层中形成复杂缝网，再以冻胶压裂液造主缝，形成大规模的连通性体积缝网。将聚丙烯酰胺类滑溜水与低分子量胍胶类冻胶压裂液复合应用，开发出了适合川中沙溪庙储层的“滑溜水＋冻胶”混合压裂液技术。其中，滑溜水具有低摩阻、高效防膨等特点；冻胶压裂液具有耐剪切、低伤害等特点；混合压裂液体系的破乳效果好、返排能力强。现场试验表明：“滑溜水＋冻胶”混合压裂液技术具有良好的储层改造效果，在G36井、G117井应用获得成功，现场降阻率达61．5％～64．8％、返排率＞40％，返排液油水界面清晰，获井口测试产油45．1 t/d。%The tight reservoir of Sichuan Shaxi Temple layer has characteristics of extremely low porosity and low permeability ,and the fracturing process requires to pump slickwater with large emission to form complex fracture networks in formation ,then pump gel fracturing fluid to create main fracture and form a large volume of connective fracture network .Due to the compos-ite application of polyacrylamide slickwater and low molecular guar gum fracturing fluid ,a mixed fracturing fluid technology of “slickwater + crosslinked gel” has been developed ,which is suit-able to Shaxi Temple reservoir in Central Sichuan .Slickwater has characteristics of low friction and high clay stable performance , crosslinked fracturing fluid has characteristics of excellent shear resistance and low core damage ,and the mixed fracturing fluid has good demulsification performance and high flowback rate .Field test results show that “slickwater + crosslinked gel”technology has good effect of reservoir stimulation ,which was successful applied in G36 well , G117 well ,the drag reduction rate reached 61 .5% ~64 .8% ,flowback rate was more than 40% , interface of the flow back fluid and the oil is clear and testing oil production achieved 45 .1t/d .
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