槽波波速CT 成像技术及其应用

槽波地震勘探因为具有分辨率高、能量衰减小的特点，在煤矿井下隐伏致灾体的地球物理勘 探中已得到了广泛的应用。但现阶段的槽波探测精度尚无法满足矿山智能化的要求。目前，物理模拟多以二维模型条件下的 Rayleigh型槽波模拟为主，Love型槽波研究较少。为了掌握 Love 型槽波的传播规律，进行了三维槽波物理模拟中的 Love 型槽波研究。首先，通过波动方程和频散曲线分析，研究了Love 型槽波的波动及质点振动特征；然后以相似性原则为基础，通过构建类比于野外采集的激发、接收、同步装置，搭建了槽波物理模拟平台；随后通过硅橡胶和树脂等材料的配比选择，制作了符合实际地层岩层属性的地震物理模型；最后通过设计的3种典型观测系统，进行槽波超声物理模拟，成功观测到了物理模型中的 Love 型槽波。通过对煤层和围岩中2条测线的波场记录和频散曲线的对比分析，特别是理论曲线的符合程度进一步验证了模拟的有效性。同时，通过对横穿断层和正常煤层的2条测线Love型槽波波场的对比发现，断层前后波场频率成分发生了以 Airy 相为分界的明显转换，而且过断层后槽波能量几乎全部被衰减。研究结果将为后续定量、精细化槽波地震勘探提供采集、处理及解释等方法技术的理论支撑。

A coal seam as a guide for seismic energy

Owing to its high resolution and low energy attenuation, channel wave-based seismic exploration has been widely applied in the geophysical prospecting of hidden disaster-causing factors in underground coal mines. However, its accuracy fails to meet the requirements of intelligent mine mining presently. At present, the analogue modeling of channel waves mostly focuses on Rayleigh-type channel waves using 2D models, leading to a lack of research on Love-type channel waves. To explore the propagation law of Love-type channel waves, this study investigated the waves in the 3D analogue modeling of channel waves. Firstly, the wave and particle vibration characteristics of Love-type channel waves are studied through the analysis of the wave equation and dispersion curve. Subsequently, based on the principle of similarity, an analogue modeling platform of channel wave is built by constructing excitation, receiving and synchronization devices similar to field acquisition. Then, through the ratio selection of materials such as silicone rubber and resin, a seismic analogue model that conforms to the actual strata properties is made. Finally, through the design of three typical observation systems, the channel wave ultrasonic physical simulation is carried out, and the Love-type channel wave in the physical model is successfully observed. Through the comparative analysis of the wave field records and dispersion curves of the two survey lines in the coal seam and the surrounding rock, especially the coincidence degree of the theoretical curve, the validity of the analogue modeling is further verified. At the same time, by comparing the Love-type channel wave field of two survey lines crossing the fault and the normal coal seam, it is found that the frequency components of the wave field underwent a significant conversion with the Airy phase as the boundary before and behind a fault, with the channel wave energy almost completely attenuated after passing through the fault. The results of this study will provide theoretical support for data acquisition, processing, and interpretation in the subsequent quantitative and refined channel wave-based seismic exploration.