用频率-波数法分析瑞利波频散曲线  

INVESTIGATION ON THE DISPERSION CURVES OF RAYLEIGH WAVE BY FREQUENCY-WAVENUMBER ANALYSIS METHOD

作　　者：张碧星[1] 鲁来玉[2] 

机构地区：[1]中国科学院声学研究所,北京100080 [2]中国地震局地球物理研究所,北京100081

出　　处：《工程地球物理学报》2005年第4期245-255,共11页Chinese Journal of Engineering Geophysics

基　　金：国家自然科学基金资助项目(10374098)

摘　　要：传统的表面波谱分析方法(SASW)采用两道互相关方法处理频散曲线,这种方法难以获取多模式的频散曲线。本文采用频率-波数(f-k)分析方法对瑞利波多模式频散曲线进行了研究和分析,选取了实际中经常碰到的三种分层介质模型,利用数值模拟方法对瑞利波的激发和传播特性进行了深入的研究,详细分析了接收道数目、源检距等参数对频散曲线的影响,获得了关于这些参数的一些重要结果,发现当源检距大于半波长(0.5λ)时利用f-k分析方法可以得到可靠的频散曲线。Cross correlation method is adopted to extract the dispersion curves of the Rayleigh wave in SASW（Spectral Analysis of Surface Wave）. Separate multi-mode dispersion curves can not be obtained by this method except the problem countered in unwrapping the phase. The dispersion curves of the Rayleigh wave are investigated by the frequency-wavenumber analysis in this paper. Three models of the layered media are considered. The excitation and propagation characteristics of the Rayleigh wave are investigated by numerical simulation. The effects of some parameters such as the number of channels and distance between the source and the first receiver on the dispersion curves are investigated in detail for three models. Some important results about the number of receiver channels, relative error, and mode jumping are obtained. It is found that good dispersion curves can be obtained by f-k analyses when the distance between the first receiver and the source is greater than 5g.

关 键 词：频散曲线 瑞利波 SASW 频率波数域 模式跳跃 

分 类 号：P631.4[天文地球—地质矿产勘探]