In order to effectively stimulate the ultra-deep shale reservoirs in southeastern Sichuan and minimize the fracturing pressure ,some technical solutions were proposed ,such as optimization of perfora-tion parameters ,acid pretreatment before fracturing ,design of slick water system with high friction reduc-ing rate ,and application of lead silt slug techniques .Through analysis and calculation ,it was decided to use the φ89 mm perforating gun with type SDP40HMX28 8 charges for perforation at 18 shots/m and phase 60° .Based on core dissolution tests and characteristics of such ultra-deep shale reservoirs ,a formula of 15.0% HCl+1.5% HF+2.0% HT corrosion inhibitor+1.5% ferric ion stabilizer was determined .Ac-cording to the stratigraphic characteristics ,a laboratory experiment was performed and it revealed a slick water system consisting of 0.2% efficient friction reducer SRFR 1+0.3% compound anti-swelling agent+0.1% compound synergist + 0 .02% defoamer ,which is stable and easy to flowback ,with viscosity of a-bout 9 12 mPa · s ,friction reducing rate than 75% and formation damage less than 10% .Field application showed that the optimized perforation parameters could meet the requirement for perforation friction reduc-tion ;acid pretreatment before fracturing enabled the pressure reduced by 10 15 M Pa;the lead silt slug tech-nique could effectively reduce the friction due to fractures curvature ,thereby reducing the fracturing pres-sure .It showed that these technical solutions could help to reduce the fracturing pressure in ultra-deep shale gas wells in the southeastern Sichuan .%为实现川东南超深页岩储层有效改造，并最大限度地降低压裂施工压力，提出了优选射孔参数、进行压前酸液预处理、设计降阻率高的滑溜水体系及采用前置粉砂段塞技术等技术对策。通过分析和计算，采用φ89 mm射孔枪配合SDP40HMX288射孔弹，60°相位和18孔/m的孔密进行射孔。利用川东南超深页岩储层的岩心进行了溶蚀试验，根据试验结果结合地层特点确定了15.0％ HCl＋1.5％ HF＋2.0％高温缓蚀剂＋1.5％铁离子稳定剂的酸液配方。根据地层特征，通过室内试验优选了配方为0.2％高效减阻剂SRFR 1＋0.3％复合防膨剂＋0.1％复合增效剂＋0.02％消泡剂的滑溜水，其性能稳定，易返排，黏度约9～12 m Pa · s ，降阻率大于75％，对地层的伤害率小于10％。现场应用表明：采用优化后的射孔参数进行射孔，可以满足降低孔眼摩阻的要求；应用优选的酸液进行压前预处理，施工压力降低10～15 M Pa；采用前置粉砂段塞技术，可以有效降低裂缝弯曲摩阻，达到降低施工压力的目的。这表明，采用提出的技术对策可以降低川东南超深页岩气井压裂施工压力。
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