Attenuation and Scattering of Short-Period Seismic Waves in the Lithosphere
Attenuation and Scattering of Short-Period Seismic Waves in the Lithosphere
复制标题
岩石圈中短周期地震波的衰减和散射
DOI：
10.1007/978-94-009-8531-5_28
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
K. Aki
中科院分区：
文献类型：
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作者：
K. Aki
在LASA等台阵上观测到的地震波前的不规则性可归因于台阵下方岩石圈的非均质性。这些非均质性对探测地震学具有重要意义，因为它们对用于震源识别的地震波形有影响。本文研究了岩石圈非均质性对短周期地震波的下列影响：(L)在地震台阵上观测到的远震P波的幅度和相位的起伏；(2)S波在岩石圈中的衰减；(3)利用局部地震的尾波的后向散射效应。我们发现，解释尾波振幅所需的后向散射能量与S波的能量损失相一致，这表明S波在岩石圈的衰减可能主要是由于散射。Q的频率依赖性及其随构造活动程度的系统变化表明，年轻活动区的非均质性标尺长度越短，速度波动幅度越大。
The irregularities in seismic wave fronts observed at arrays such as LASA can be ascribed to heterogeneities in the lithosphere beneath the array. These heterogeneities are important in detection seismology because of their effect on seismic waveforms to be used for source identification.The present author has studied the following effects of heterogeneities in the lithosphere on short period seismic waves: (l) the fluctuation of the amplitude and phase of teleseismic P waves observed at a seismic array, (2) the attenuation of S waves through the lithosphere, and (3) the backscattering effect using coda waves of local earthquakes.We found that the backscattered energy required to explain coda amplitude agrees with the loss of energy from S waves, suggesting that attenuation of S waves in the lithosphere may be primarily due to scattering. The frequency dependence of Q and its systematic change with the degree of tectonic activity suggests a trend that the scale length of inhomogeneity is shorter and the magnitude of velocity fluctuation is greater for younger and more active regions.
影响因子：
--
作者：
K. Aki;A. Christoffersson;E. Husebye
通讯作者：
K. Aki;A. Christoffersson;E. Husebye