Spatiotemporal distribution of very-low frequency earthquakes in Tokachi-oki near the junction of the Kuril and Japan trenches revealed by using array signal processing
Spatiotemporal distribution of very-low frequency earthquakes in Tokachi-oki near the junction of the Kuril and Japan trenches revealed by using array signal processing
复制标题
DOI：
10.1186/bf03352839
复制
发表时间：
2008-01-01
影响因子：
3
通讯作者：
Ito, Yoshihiro
中科院分区：
文献类型：
--
作者：
Asano, Youichi;Obara, Kazushige;Ito, Yoshihiro
我们已经开发了一种信号处理方法，在日本密集和广泛分布的倾斜仪站记录的阵列数据，并分析了在过去5年中记录的数据。对滤波后的地震图进行分析，以检测相干地震波并估计震中。为了识别仅具有低频能量的甚低频地震（VLFE），我们从所有检测到的事件中仅选择了日本气象厅提供的地震目录中未列出的事件。所获得的VLFEs的震中估计不仅分布在沿着南海海槽，在那里的事件发生在逆断层上的增生棱柱体发育，但在十胜冲没有增生。这一结果表明，即使在这样一个地区，VLFE可以发生在一个浅的部分板块边界比普通地震的孕震区和/或在一个变形区的覆盖板块沿着俯冲带没有加积。
We have developed a signal-processing method for array data recorded at densely and widely distributed tiltmeter stations in Japan and analyzed the data recorded during the last 5 years. Filtered seismograms were analyzed to detect coherent seismic waves and estimate the epicenters. In order to identify very-low frequency earthquakes (VLFEs) with only low-frequency energies only, we selected only events not listed in the earthquake catalogue provided by the Japan Meteorological Agency from all of the detected events. The epicenters of the obtained VLFEs were estimated to be distributed not only along the Nankai Trough, where the events occurred on the reverse faults in the well-developed accretionary prism, but also in Tokachi-oki without accretion. This result suggests that even in such a region, VLFEs can occur on a shallower portion of the plate boundary than the seisrnogenic region of ordinary earthquakes and/or in a deformed area of the overriding plate along the subduction zone without accretion.