• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Earth, planets and space: EPS >High-resolution aftershock observations in the source region of the 2004 mid-Niigata Prefecture Earthquake
【24h】

High-resolution aftershock observations in the source region of the 2004 mid-Niigata Prefecture Earthquake

机译：2004年新泻县中地震震源区的高分辨率余震观测

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We deployed an extremely dense temporal seismic network in the source region of the 2004 mid-Niigata Prefecture Earthquake (thrust fault) on October 23, 2004, Japan. The seismic network consisted of 145 temporary seismic stations within a 30 km squared and had been kept within approximately a month after the mainshock. High accurate hypocenters of 708 events were determined by inverting the arrival times using double-difference earthquake location algorithm. The aftershocks along the mainshock ( M w = 6.6) and the largest aftershock ( M w = 6.3) rupture zones are distributed on two 60° westward-dipping planes, located approximately 5 km apart. Conversely, the Oct. 27 aftershock ( M w = 5.8) occurred on an eastward dipping plane with a dip angle of 25° that was conjugate to the mainshock fault plane. Most of aftershocks at both northeastern and southwestern edges occurred at shallow depths with eastward-dipping planes. Epicenters of aftershocks in the southwestern region are aligned along N15°E, and rotate approximately 20° counterclockwise from the strike of the mainshock fault. This rotation of the aftershock alignments coincides with the rotation of anticline axes in the southwestern area of the source region. Furthermore, distributions of station corrections for a one-dimensional velocity model suggest that the seismic velocity at the western side of the Muikamachi-fault is lower than that at the eastern side. It is also inferred that the velocity structures in the hangingwall vary along the fault strike. The average velocity in the mainshock rupture area is higher than the periphery in the hangingwall, especially compared with the southwestern side of the hypocenter.
机译：2004年10月23日，我们在2004年新泻县中部地震（冲断层）的震源区部署了一个极为密集的时空地震网络。地震网络由30平方公里内的145个临时地震台组成，并在主震发生后约一个月内得到了保存。通过使用双差地震定位算法反转到达时间来确定708个事件的高精度震源。沿主震（M w = 6.6）的余震和最大的余震（M w = 6.3）破裂带分布在两个向西倾斜60°的平面上相距5公里。相反，10月27日的余震（M w = 5.8）发生在向东的倾角，倾角为25°，与主震断层共轭。东北和西南边缘的大部分余震都发生在浅水深处，向东倾斜。西南地区余震的震中沿N15°E对齐，并从主震断层走向逆时针旋转约20°。余震路线的这种旋转与源区西南地区背斜轴的旋转一致。此外，一维速度模型的台站校正分布表明，Muikamachi断层的西侧的地震速度低于东侧的地震速度。还可以推断出，吊壁中的速度结构沿断层走向变化。主震破裂区的平均速度高于上盘壁的外围，特别是与震源的西南侧相比。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号