Source Processes of 15 September 1998 M 5.0 Sendai, Northeastern Japan, Earthquake and Its M 3.8 Foreshock by Waveform Inversion
Source Processes of 15 September 1998 M 5.0 Sendai, Northeastern Japan, Earthquake and Its M 3.8 Foreshock by Waveform Inversion
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1998年9月15日日本东北部仙台M 5.0地震及其M 3.8前震波形反演震源过程
DOI：
10.1785/0120000240
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发表时间：
2001
影响因子：
3
通讯作者：
M. Kamiyama
中科院分区：
文献类型：
--
作者：
T. Okada;N. Umino;Y. Ito;T. Matsuzawa;A. Hasegawa;M. Kamiyama
1998年9月15日，日本东北部仙台市发生里氏5.0级地震，造成该市部分地区轻微损坏。它位于长町利府断层约12公里深处，这是一条穿过城市中心的活跃逆断层。我们通过经验格林函数方法研究了地震的破裂过程及其最大前震（M 3.8）。我们使用附近密集的强运动阵列以及短周期和宽带站记录的波形数据。主震波形反演结果表明，其破裂区的空间范围约为3×3 km 2 ，与余震区的空间范围大致一致。大部分时间的释放都包含在两个粗糙的地方。通过均匀台站方法精确重定位的余震表明，在主震释放力矩相对较小的地区，余震活动性较高。最大前震（M 3.8）的破裂发生在主震开始前 6 分钟，大约在主震震源处。其破裂区域半径约为300 m，与主震的凹凸不平没有强烈重叠。
A moderate earthquake ( M 5.0) occurred on 15 September 1998 in Sendai City, northeastern Japan, causing slight damage in a portion of the city. It was located at about 12-km depth on the Nagamachi-Rifu fault, an active reverse fault passing through the center of the city. We investigate rupture processes of the earthquake and its largest foreshock ( M 3.8) by an empirical Green9s-function method. We use waveform data recorded by nearby dense strong-motion arrays and by short-period and broadband stations. Waveform inversion results for the mainshock show that the spatial extent of its rupture area is about 3 × 3 km 2 , which is roughly consistent with that of the aftershock area. Most of the moment release was contained in two asperities. Aftershocks precisely relocated by a homogeneous-station method show that their activity is high in areas with a relatively small amount of moment release of the mainshock. Rupture of the largest foreshock ( M 3.8) that occurred 6 min before the mainshock started approximately at the mainshock hypocenter. Its rupture area, with a radius of about 300 m, does not strongly overlap with the asperities of the mainshock.
影响因子：
3
作者：
J. Mori;S. Hartzell
通讯作者：
J. Mori;S. Hartzell