• 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 >Urgent aftershock observation of the 2004 off the Kii Peninsula earthquake using ocean bottom seismometers
【24h】

Urgent aftershock observation of the 2004 off the Kii Peninsula earthquake using ocean bottom seismometers

机译：使用海底地震仪对2004年基伊半岛地震进行紧急余震观测

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

摘要

The 2004 off the Kii Peninsula earthquake occurred on September 5, 2004. Knowing the precise aftershock distribution is important for understanding the mechanism of this earthquake. However, the hypocenter of the main shock was located more than 100 km offshore from the nearest station of the land observation network. In the three days after the main shock, we started ocean bottom seismometer (OBS) observation in order to determine the precise distribution of the aftershocks. We assumed a seismic velocity structure for the hypocenter calculation, based on the results of previous seismic refraction study. The station corrections were incorporated to locate the hypocenter precisely. The hypocenters located within an area covered by five OBSs show relatively small errors. It is found that the OBS-located hypocenters are located about 5.5 km east-southeast from those by JMA and the depth range of the aftershocks is about 5-25 km just beneath the Nankai trough axis. The aftershock hypocenters can be grouped into two clusters at different depths of about 10 km and about 20 km. It is inferred that the main shock also has a depth of 5-25 km. Since this extent of the main shock was larger than one of the oceanic crust of the Philippine Sea plate, the fault plane of the main shock extended at the upper most mantle of the Philippine Sea plate. Although we cannot assign the actual fault plane of the main shock form our observation results, it is clarified that intra-plate earthquakes occurred near the trench region. Our OBS result supports that the main shock was the earthquake not at the plate boundary but within the bending Philippine Sea plate near the trough axis.
机译：2004年基伊半岛地震发生在2004年，发生在2004年9月5日。了解精确的余震分布对于理解地震的机理很重要。但是，主震的震中位于离陆地观测网最近的站100公里以外的地方。在主震发生后的三天内，我们开始进行海底地震仪（OBS）观测，以确定余震的精确分布。根据先前地震折射研究的结果，我们假设地震速度结构用于震源计算。合并了测站校正以精确定位震源。位于由五个OBS覆盖的区域内的震源显示出相对较小的误差。发现位于OBS的震源位于距JMA震源东南约5.5 km处，余震的深度范围位于南开海槽轴下方约5-25 km。余震震源可以分为大约10 km和大约20 km不同深度的两个簇。据推测，主震的深度也为5-25 km。由于主震的这一程度大于菲律宾海板块的洋壳之一，因此主震的断层面在菲律宾海板块的最上层延伸。尽管我们无法从观测结果中分配出主震的实际断层面，但可以澄清的是，板内地震发生在沟槽区域附近。我们的OBS结果支持主要地震不是在板块边界而是在海槽轴附近菲律宾海弯曲板块内发生的地震。

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