基于射线追踪的微地震多波场正演模拟  

The Multi-wave Field Forward Simulation of Micro-seismic Based on Ray Tracing

作　　者：宋维琪[1] 杨晓东[1] 

机构地区：[1]中国石油大学(华东)地球科学与技术学院,东营257061

出　　处：《地球物理学进展》2012年第4期1501-1508,共8页Progress in Geophysics

摘　　要：对于微地震正演模拟,本文以射线追踪的原理为基础,对两点间的射线追踪问题进行了研究,应用二分算法、改进二分算法和微变网格算法对水平层状匀速模型、弯曲层状匀速模型和复杂地质模型进行射线追踪,使得计算效率和适用范围都得到了很大的改善.文中对每种算法误差范围和计算效率进行了对比验证,对于不同的地质模型,选用合适的算法才能在计算速度和精度上得到双重保证,最后正演模拟了多波三分量记录.在模型建立上引入了超薄层概念,并在前人模拟的直达波、透射波、反射波基础上拟了折射波,使正演模拟的多波场信息更丰富.文中的应用实例及模型结果表明:与二分法相比,改进二分法能够对弯曲界面进行射线追踪,并能保证结果的精度.弯曲层状模型中,改进二分法与微变网格法相比计算速度有显著提高,能够应用到资料的反演中.The ray tracing method is a sort of approximate calculation method for wave field which has characteristics of rapid and efficient calculation, direct and clear ray path. Based on the principle of ray tracing in microseimic forward, lots of research on ray tracing between two points have been done in this paper. Aiming at horizontal layered uniform motion model, curved layered uniform motion model and complex geological model, the corresponding ray tracing algorithms, such as the dichotomy, the improved dichotomy and micro-variable mesh algorithm, are scientifically designed to improve the computational efficiency and application scope greatly on the premise of original trial ray method. The error range and computational efficiency for each algorithm in this paper has been compared and verified. A proper algorithm is selected for different geological model in order to achieve fast calculation speed and high accuracy simultaneously. , and then forward simulation are carried out for multi-wave field three-component records. The notion of ultra-thin layer has been introduced into this paper during modeling and the refraction wave is taken into consideration for simulation on the premise of existing simulation for direct wave, transmission wave and reflection wave. The multi-wave field information by forward simulation is richer than before. The results of models and application examples in this paper show that the improved dichotomy can achieve ray tracing for curved interface with high accuracy compared with the dichotomy. In the curved layered model, the improved dichotomy possesses higher calculation speed than the micro-variable mesh algorithm and could be applied in inversion.

关 键 词：微地震 射线追踪 地质模型 正演模拟 多波场 

分 类 号：P631[天文地球—地质矿产勘探]