A new method for earthquake depth determination: stacking multiple-station autocorrelograms
A new method for earthquake depth determination: stacking multiple-station autocorrelograms
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地震深度测定新方法：叠加多站自相关图
DOI：
10.1093/gji/ggu044
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发表时间：
2014-05
影响因子：
2.8
通讯作者：
Wen, Lianxing
中科院分区：
文献类型：
--
作者：
Zhang, Miao;Tian, Dongdong;Wen, Lianxing
精确测定地震深度很重要，但也特别具有挑战性。本文提出了一种利用多台自相关图叠加确定震源深度的新方法。SMAC方法的基本思想是通过自相关和叠加增强相干地表反射能量，并利用地表反射能量确定震源深度。自相关有效地提高了与震源深度相关的地震相的能量，而叠加阵列数据的自相关图进一步提高了能量的信噪比。该程序适用于使用主SH波和尾波。利用尾波，该方法通过在一系列地震观测上叠加尾波自相关来提取震源和地表之间的双向走时。SMAC利用主SH波，利用自相关方法研究了下行Moho反射SmS波和上行Moho反射sSmS波的干扰。然后将自相关图沿着理论差分sSmS-SmS走时叠加，并确定源深度为产生最大叠加能量的深度。合成测试证明了SMAC程序的有效性。作为一个应用实例，我们应用SMAC方法确定了日本岛发生的一次地震的震源深度。同时使用主SH波和其尾波的程序产生强大的表面反射能量和一致的震源深度。假定地壳平均速度的不确定性为10%，深度估计误差小于1公里。
S U M M A R Y Accurate determination of earthquake depth is important, but particularly challenging. We develop a new method to determine the earthquake source depth by stacking multiple-station autocorrelograms (SMAC) of seismic data. The basic concept of SMAC method is to enhance the coherent surface reflected energy by autocorrelation and stacking, and uses the surface reflected energy to determine the source depth. Autocorrelation effectively enhances the energy of the seismic phases related to the source depth, while stacking the autocorrelograms of array data further improves the signal-to-noise ratio of the energy. The procedures are applied using both the main SH waves and the coda. Using coda waves, the method extracts the two-way traveltime between the source and the surface by stacking the coda wave autocorrelations over an array of seismic observations. Using the main SH waves, SMAC explores the interference of the down-going Moho reflected SmS wave and up-going surface bounced Moho reflected sSmS wave by autocorrelation. The autocorrelograms are then stacked along theoretical differential sSmS–SmS traveltime predicted for all potential source depths, and the source depth is determined to be the one that produces the maximum stacking energy. Synthetic tests demonstrate the validity of the SMAC procedures. As an example of application, we apply the SMAC method to determine the source depth of an earthquake occurring in Japan Island. The procedures of using both main SH waves and their coda waves yield robust surface reflected energy and a consistent source depth. The error of the depth estimation is less than 1 km assuming an uncertainty of 10 per cent in the averaged crust velocity.
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影响因子：
3
作者：
R. Clayton;B. Engquist
通讯作者：
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影响因子：
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通讯作者：
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通讯作者：
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影响因子：
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作者：
Wen, Lianxing
通讯作者：
Wen, Lianxing