Emergence of broadband Rayleigh waves from correlations of the ambient seismic noise
Emergence of broadband Rayleigh waves from correlations of the ambient seismic noise
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DOI：
10.1029/2004gl019491
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发表时间：
2004-04
影响因子：
5.2
通讯作者：
N. Shapiro;M. Campillo
中科院分区：
文献类型：
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作者：
N. Shapiro;M. Campillo
我们证明，相干信息的地球结构可以从周围的地震噪声中提取。我们计算了几天的地震噪声的垂直分量记录的互相关，这些记录是在距离从大约100公里到超过2000公里的不同台站对上进行的。相干宽带色散波列清楚地出现了群速度，类似于使用弹道表面波约束的全球瑞利波层析成像图预测的群速度。这些结果表明，相干瑞利波可以从环境地震噪声中提取出来，并且可以在很宽的周期范围内测量它们的频散特性。这为新型面波测量提供了一个来源，可以针对无法用弹道波采样的许多路径获得这些测量，因此可以显着提高地震图像的分辨率。
We demonstrate that the coherent information about the Earth structure can be extracted from the ambient seismic noise. We compute cross‐correlations of vertical component records of several days of seismic noise at different pairs of stations separated by distances from about one hundred to more than two thousand kilometers. Coherent broadband dispersive wavetrains clearly emerge with group velocities similar to those predicted from the global Rayleigh‐wave tomographic maps that have been constrained using ballistic surface waves. Those results show that coherent Rayleigh waves can be extracted from the ambient seismic noise and that their dispersion characteristics can be measured in a broad range of periods. This provides a source for new types of surface‐wave measurements that can be obtained for numerous paths that could not be sampled with the ballistic waves and, therefore, can significantly improve the resolution of seismic images.