落锤震源不同参数激发的数值模拟研究

Numerical Simulation of Hammer Source with Different Excitation Parameters

本文通过研究落锤震源的物理模型,利用有限元方法,对震源激发到子波形成的全过程进行数值模拟研究。从激发参数角度,分别对软地表(土壤)和硬地表(岩石)条件下的不同落锤震源参数的激发进行数值模拟,分析不同震源参数对子波能量和频谱的影响,并比较不同地表岩性介质对震源参数变化的响应。同时将模拟结果同已有的数据采集研究和实验研究进行对比,以说明其有效性。研究结果显示落锤震源的激发效果同重锤质量、冲击速度、基板大小和基板材料的关系,为浅地表地震勘查中落锤震源参数的选择提供了参考依据。

The excitation results of hammer sources are determined by the mass of the hammer, the impact velocity, the size and materials of the base plate. By studying the physical model of hammer source and using finite element methods, we numerically simulated the whole process of the hammer source excitation to the formation of the seismic wavelet, and then calculated and analyzed the wavelet. From the angle of excitation parameters, we carried out numerical simulations of seismic excitation with different parameters on soil and rock medium. Then we analyzed the impacts of different source excitation parameters on wavelet and the impacts of mediums. This study provides a reference basis for choosing excitation parameters of hammer source to improve the prospect quality in shallow surface seismic exploration.