...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Earth and Planetary Science Letters: A Letter Journal Devoted to the Development in Time of the Earth and Planetary System >An episode of fault-valve behaviour during compressional inversion? The 2004 M(J)6.8 Mid-Niigata Prefecture, Japan, earthquake sequence
【24h】

An episode of fault-valve behaviour during compressional inversion? The 2004 M(J)6.8 Mid-Niigata Prefecture, Japan, earthquake sequence

机译：压缩反演过程中是否出现断层阀行为？日本新泻中部2004 M（J）6.8地震序列

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Principal ruptures of the 2004 Mid-Niigata Prefecture sequence involved close-to-pure reverse slip on a 50-60 degrees WNW dipping fault system uplifting a Miocene rift basin on its hanging wall, consistent with geological evidence for ongoing compressional inversion in the region since the Late Pliocene. The M(J)6.8 mainshock was followed by four other M-J > 6 shocks (all with hypocentres in the 7-12 km depth range) and a rich aftershock sequence defined a criss-crossing network of reverse-slip rupture planes dipping 50-60 degrees WNW and 25-35 degrees ESE. The steep rupture planes dip close to the maximum for reverse-fault earthquakes and are poorly oriented for frictional reactivation assuming horizontal maximum compressive stress. In contrast, the subsidiary ESE-dipping thrusts appear optimally oriented in the stress field. The combined reactivation of existing, unfavourably oriented reverse faults and optimally oriented thrusts requires high but probably variable fluid-overpressuring within the rock-mass. Evidence for overpressures in and around the seismogenic fault system comes from borehole measurements in the hanging-wall sedimentary basin plus a range of anomalous seismological and electrical characteristics which also suggest an overpressured mid-crust below the seismogenic zone. Minor postseismic effusion of anomalously warm, saline formation fluids was recorded from the aftershock area: similar discharges characterize the epicentral areas of historic earthquakes in the Niigata region. The rupturing of unfavourably oriented faults in a fluid-overpressured compressional regime - together with the swarm-like character of the aftershock activity and the evidence of postseismic discharge - are all suggestive of a 'fault-valve' episode involving upwards migration of fluids from compartmentalized fluid-overpressures within the seismogenic zone. (c) 2007 Elsevier B.V. All rights reserved.
机译：2004年新泻县中部层序的主要破裂包括在50-60度WNW倾覆断层系统上近乎完全的反向滑移，使中新世裂谷盆地的悬挂壁隆升，这与该地区自从那时以来正在进行的压缩反演的地质证据一致。上新世晚期。 M（J）6.8主震之后是其他四次MJ> 6次电击（均在7-12 km深度范围内有震中），丰富的余震序列定义了反向滑动破裂面纵横交错的网络（倾角50-60） WNW和ESE 25-35度。对于反向断裂地震，陡峭的破裂面倾角接近最大值，并且假设水平最大压缩应力，则对于摩擦复活而言定向不佳。相反，辅助ESE浸入推力在应力场中表现出最佳取向。现有的，不利于定向的逆向断层和最佳定向的推力的组合重新激活，需要在岩体内施加较高但可能可变的流体超压。地震断层系统及其周围地区超压的证据来自于悬挂壁沉积盆地的钻孔测量以及一系列异常的地震和电学特征，这也暗示了地震成因带下方的中地壳超压。在余震区记录到了异常温暖的盐水形成液的较小的地震后渗出：新泻地区历史地震的震中区域具有类似的排放特征。流体超压压缩状态中定向不良的断裂破裂，以及余震活动的类群特征和地震后泄出的证据，都暗示了“断层阀”事件的发生，这涉及到流体从隔室向上迁移的情况。地震发生区内的流体超压。 （c）2007 Elsevier B.V.保留所有权利。

著录项

相似文献

  • 外文文献
  • 中文文献
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