GPS observations of postseismic deformation for the 1995 Hyogo‐Ken Nanbu Earthquake, Japan
GPS observations of postseismic deformation for the 1995 Hyogo‐Ken Nanbu Earthquake, Japan
复制标题
1995 年日本兵库县南部地震震后变形的 GPS 观测
DOI：
10.1029/97gl00375
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发表时间：
1997
影响因子：
5.2
通讯作者：
K. Hirahara
中科院分区：
文献类型：
--
作者：
T. Nakano;K. Hirahara
在1995年兵库县南部地震后2天内开始的11个月的GPS观测中，发现了地震后地壳的显著变形，在一些台站达到了20 mm。震后和同震变形的比较表明，在位移方向上有相似的模式。我们试图通过研究观测到的震后变形的时间依赖性来确定主要的弛豫机制。我们考虑了三种模型：指数模型、幂律模型和非线性衰减模型。然而，这三个时间依赖模型中的每一个都可以很好地解释观察到的数据。在指数弛豫模型的情况下，弛豫时间常数估计为约50天。在幂律模型中，指数p接近1.0;这与大森余震序列衰减规律的p值几乎相同。这表明震后形变的机制可能与余震的产生机制有关。
11‐months of GPS observations, which started within 2 days of the 1995 Hyogo‐ken Nanbu earthquake, detected significant postseismic crustal deformation that reached 20 mm at some stations. A comparison of postseismic and coseismic deformation shows a similar pattern in the direction of displacements. We tried to determine the predominant relaxation mechanism by examining the time dependence of observed postseismic deformation. We considered three models: an exponential, a power‐law, and a logarithmicaly decaying model. However, each of these three time‐dependent models can explain the observed data, equally well. In case of the exponential relaxation model, the relaxation time constant was estimated to be about 50 days. In the power‐law model, the index p was nearly 1.0; this is almost the same as the p value of Omori's decay law of aftershock sequences for this event. This suggests that the mechanism causing postseismic deformation may be related to that producing aftershocks.