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川西新场气田蓬莱镇气藏是一个纵向上互相叠置( 可细分为3 个气藏) 、低孔渗、高含水饱度的致密碎屑岩定容封闭干气藏.由于气藏的致密一近致密特征,气井的自然产能较低,不经储层改造几乎不能形成工业产能,故常采用变排量、顺序注入多段不同的压裂液、加置尾砂等压裂工艺,以造长缝为主要目的.作者推导和建立了注入三段幂律体压裂液时水平裂缝延伸的数学模型,并在 LOWE 等人支撑运移分布模型的基础上,研制了水平裂缝压裂设计软件.通过实例计算,对影响水平裂缝压裂效果的可控因素进行了分析,认为:在川西蓬莱镇组气藏,由于 K H 值较低,宜采用大液量、小排量、低砂比的施工方式;采用部分后置高稠度系数压裂液的增产效果与全部使用高稠度系数压裂液的增产效果接近;采用部分后置大颗粒石英砂工艺与全部使用大颗粒石英砂增产效果接近.“,”The Penglaizhen gas reservoir of Xinchang gas field in west Sichuan is a longitudinally overlapped (can be subdivided into three gas reservoirs) and tight clastic rock constant volume confined dry gas reservoir with low porosity,low permeability and high water saturation.The natural productivity of the gas wells is relatively low due to the dense/near dense characteristics of the gas reservoir and the commercial productivity can almost not be achieved without reservoir reformation.For this reason,the fracturing technologies,such as changing discharge capacity,successively pumping many “sections” of different fracturing fluids and adding tail sands,etc.,have been often used,which main target is to create long fractures.A mathematical model has been derived and set up for the horizontal fracture extending while the three sections of power law fracturing fluid are pumped and a software for horizontal fissure fracturing design has been developed on the basis of the supporting migrating distributing model by Lowe et al.Through the calculation of an example,the controllable factors influencing the fracturing results of horizontal fissures are analyzed and it is considered that for the Penglaizhen formation gas reservoir in west Sichuan,it is suitable to adopt the operating way with a great quantity of fluid,low pumping rate and small sand ratio due to a quite low KH value;that the well stimulation effect by partially using the post pad fracturing fluid with high viscosity coefficient is similar to that by entirely using the fracturing fluid with high viscosity and that the well stimulation effect by partially using post pad megagrained quartz sands is similar to that by entirely using megagrained quartz sands.