【摘要】 本文基于多尺度阵列嵌套组合的方式,利用频率-贝塞尔变换法(Frequency-Bessel, F-J方法)提取背景噪声面波频散信息,通过多个阵列融合的频散曲线反演得到宾川气枪发射台周边不同深度的横波速度结构.结果显示:浅层一阶面波频散信息的加入,使得基阶反演结果更加收敛,反演深度加深到8 km;深度在8 km以下的结构的研究利用多尺度阵列(密集台阵—宾川气枪台网—云南区域地震台网)嵌套组合的方式,面波基阶低频信息从0.55 Hz拓宽到0.008 Hz,使横波速度结构的反演深度显著增加,同时对反演过程提供约束,使得70 km深度以上的横波速度更收敛.由此本文所得的横波速度结构为该区地下结构的探测提供基础,多尺度阵列嵌套组合频散谱的研究方式也为以后区域结构的研究提供一种新的方法和思路.更多还原

【Abstract】 Based on a nested combination style of multi-scale arrays, we used the frequency-Bessel transform method to extract dispersion information on surface waves from ambient noise, then inverted the shear wave velocity structure at different depths of the area surrounding the Binchuan airgun source launcher with multi-scale fusion dispersion curves. Results show that using dispersion information of multi-modes surface waves can make the inversion result be more convergence and inversion depth increase to 8 km. As for the structure below the depth 8 km, using the nested combination style of multi-scale arrays(dense array-Binchuan airgun seismic network-Yunnan region seismic network) can broaden the lowest frequency of fundamental surface waves from 0.55 Hz to 0.008 Hz, so that the inversion depth of shear waves increases significantly. Meanwhile the inversion results of shear waves are more convergent above 70 km depth. The shear wave structure from this work could provide a basis for detecting underground structure of the study area, and the nested combination style of multi-scale arrays dispersion spectra provides a new approach for research of regional structure in the future.更多还原