Abstract：On the basis of zero-order ray and paraxial ray theories, seismic wave beam method has been rapidly developed for the study of seismic wave field. The Green function constructed by seismic beams with different emergence directions plays an important role in the wave field study. Based on the Gaussian beam, we first give the construction methods of focused beam, dynamic focused beam, adaptive focused beam and Fresnel beam, and then analyze in detail their beam width, wave front curve and the amplitude of the central ray. After that, using the steepest descent method, we derive the weighted coefficient of Green function when the initial beam parameter is dynamically chosen, and discuss systematically the accuracy of Green function constructed with different seismic beams and its influential factors. This work might provide some references for the future study of seismic wave beam modeling and imaging.
杨继东, 黄建平, 吴建文, 王欣, 李振春. 不同地震波束构建格林函数的精度影响因素分析[J]. 石油地球物理勘探, 2015, 50(6): 1073-1082.
Yang Jidong, Huang Jianping, Wu Jianwen, Wang Xin, Li Zhenchun. Accuracy factors of Green function constructed with different seismic wave beams. OGP, 2015, 50(6): 1073-1082.
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