The mainstream method for extracting shale gas involves hydraulic fracturing to create fracture networks. However, as extraction depth increases, notable issues such as rapid production decline, low recovery rates, high water consumption, and resource waste become apparent. Identifying new and efficient auxiliary rock-breaking technologies is crucial for overcoming these challenges. The laser, successfully utilized in industrial production, medical treatment, and technological research, offers unique features such as good directionality, coherence, and high energy density, providing novel possibilities for addressing the limitations of existing deep reservoir transformation. This research focuses on a novel laser-assisted rock-breaking technology, with shale featuring different bedding angles as the subject of investigation. The investigation methodically explored how shale responded to thermal fracture at high temperatures when exposed to laser irradiation with different spot diameter. It investigates the spatiotemporal evolution characteristics of the shale temperature field under laser irradiation, the propagation features of cracks on shale surface, and the physicochemical fracture mechanisms. The research yields the following results: (1) The region of thermal influence of the irradiation surface can be divided into three regions based on the change of rise curve of temperature in the shale surface. (2) Based on the scanning electron microscopy (SEM) testing, combined with the macroscopic and microscopic morphological characteristics of shale fracture surfaces, it reveals significantly distinct zoning characteristics in the roughness of the rock sample’s fracture surfaces after laser irradiation. (3) The thermal fracturing process of shale under laser irradiation involves chemical reactions of constituent minerals and stress generated by the thermal expansion of shale oil in the reservoir. (4) The damage and fracture of shale under the irradiation of laser show significant bedding effect, and there are three modes of rock sample failure: Pattern T (thermal failure), Pattern T-B (thermal and bedding synergistic failure), and Pattern B (bedding failure). The research findings presented in this article serve as a foundation and reference for the theory and technology of laser-assisted shale gas extraction.

Rock breaking is one of the most basic issues in deep underground engineering. Water plays an important role in the rock response under microwave radiation. Consequently, microwave radiation experiments using red sandstone with different water contents were conducted. The damage characteristics and ultrasonic properties of red sandstone after microwave radiation were primarily investigated, and the representative conclusions were drawn as follows: With the increase in water content, the time of complete formation of the rupture surface of the rock sample gradually decreased, and the decreasing range gradually increased. When the fracture surface is completely formed, the samples with a higher water content have more powdery rock cuttings and less surface roughness. The damage degree of the samples does not increase significantly with the increase in the water content when the sample is radiated at the same time. As the microwave radiation time is increased, the damage degree of the sample will increase significantly. Through the ultrasonic velocity test, it can be suggested that the sample exhibits obvious zonal damage characteristics under the action of a microwave. Generally speaking, it is a very effective means of improving the degree of microwave attenuation of the rock by increasing the water content of the rock mass.