基于甲烷原位燃爆压裂页岩试验获得燃爆关键参数(燃爆压力、燃爆速度、峰值升压时间)的变化规律，通过无量纲分析得到页岩储层应力波衰减规律，结合有限元软件ANSYS/LS-DYNA建立不同工况模型，分析燃爆对页岩产生的裂缝条数以及页岩损伤演化等规律。结果表明，甲烷与氧气发生燃爆时的压力约为初始压力的30倍，峰值升压时间为85 μs；页岩储层内应力波峰值应力与比距离之间为指数关系；提高加载速率可以在燃爆孔周边形成多条裂缝；与裸眼完井相比，套管的存在使井壁附近压力变小，沿着初始裂缝方向出现Ⅰ型裂纹扩展，扩展后的射孔长度增加47 %。

Methane in-situ explosion fracturing of shale is a revolutionary technology that utilizes the methane analyzed from shale reservoirs and the input combustion aids to carry out explosion reactions, thereby forming a three-dimensional fracture network in in-situ fracturing of shale reservoirs. This study conducted explosion experiments to investigate the variation patterns of key parameters of explosion (i.e. explosion pressure, explosion speed, rise time of peak pressure). We obtained the attenuation patterns of stress wave in shale reservoir through dimensionless analysis. We used the finite element software ANSYS/LS-DYNA to establish models of different working conditions for analyzing the number of cracks and damage evolution patterns of shale caused by explosion. Results show that: 1) The pressure during the methane/oxygen explosion is about 30 times the initial pressure. The rise time of peak pressure is 85 μs. 2) Peak stress of the stress wave and the specific distance in the shale reservoir under the explosion load are exponentially related. 3) The increase in loading rate could form multiple cracks around the explosion hole. 4) Compared with open hole completion, the presence of casing reduces the pressure near the wellbore wall, causing type Ⅰ cracks to extend along the initial fracture direction. The perforation length after extension increasesby 47 % compared to the original length.