甲烷原位燃爆压裂技术是利用页岩储层原位解析的甲烷气体与人工注入的助燃剂混合燃爆，从而压裂页岩储层形成可供甲烷气体运移的有效裂缝网络的变革性技术。利用自主研发的燃爆系统，获得甲烷−氧气燃爆压力曲线特征，结合理论模型和数值模拟方法研究了甲烷−氧气燃爆压力载荷作用下深部页岩射孔孔道周围有效裂缝网络的发育特征，并对其进行了定量分析。研究结果表明：初始应力条件对岩体应力分布状态具有明显的影响，更大的初始应力偏差导致更高的应力集中；甲烷−氧气燃爆压力的平均升压时间为85 μs；初始地应力对裂纹网络的发育具有明显的抑制作用，各向同性初始应力条件下，裂纹发育均匀呈圆形辐射状，而各向异性时，裂缝更倾向于更高初始应力方向生长，且倾向程度弱于爆炸压裂；燃爆压裂能够有效减小燃爆破碎区域面积，更有利于形成更多、更长径向裂缝；燃爆峰值压力增高对于径向裂缝末端的环向裂缝生长具有促进作用，更有利于沟通储层内天然裂缝构造复杂裂缝网络；甲烷−氧气燃爆载荷下，页岩破裂(有效裂缝)和破碎损伤阈值D_s分别选取为0.15、0.70，裂缝发育率P_s与损伤阈值D_s间数学表达近似为幂函数；E−10、E−40、E−80工况条件下的有效裂缝发育率分别为18.92%、14.11%、8.85%，燃爆峰值压力的增高能够明显促进有效裂缝发育率的增加，促进形成高度复杂裂缝网络。

The methane in-situ explosion fracturing technology is a revolutionary technology that uses methane gas obtained in-situ in shale reservoirs and artificially injected combustion promoters to form an effective fracture network for methane gas transport. The self-developed explosion system was used to obtain the characteristics of methane-oxygen detonation pressure curve. The development characteristics of the effective fracture network around the deep shale perforation channel under methane-oxygen detonation pressure load were studied by theoretical model and numerical simulation method. The results show that the stress distribution state of the rock mass is significantly impacted by the initial stress conditions, and a higher stress concentration occurs with a larger initial stress deviation. The average boost of methane-oxygen detonation pressure is 85 μs. Under the condition of isotropic initial stress, the fracture development is uniform and circular radial. When initial stress is anisotropic, the fracture tends to grow in the direction of higher initial stress, but the tendency degree is weaker than that of explosive fracturing. The area of the explosion shattering area can be effectively reduced by the explosive fracturing technology, which is more conducive to the formation of more and longer radial fractures. The increase of peak detonation pressure promotes the development of circumferential fracture at the end of radial fractures, making it more conducive to connecting natural fractures in the reservoir to construct complex fracture networks. Under methane-oxygen detonation load, the shale rupture (effective fracture) and shattering damage threshold Ds were selected as 0.15 and 0.70, respectively. The mathematical expression between the fracture development rate P_s and the damage threshold D_s was approximated as an exponential function. The effective fracture development rates under the E−10, E−40 and E−80 conditions were 18.92%, 14.11% and 8.85%, respectively. The increase of the effective fracture development rate and the formation of a highly complex fracture network can be significantly promoted by increasing the peak pressure of detonation.