• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Current Science: A Fortnightly Journal of Research >Recent Indian earthquakes
【24h】

Recent Indian earthquakes

机译：印度最近的地震

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

The last decade of the 20th century has seen much progress in comprehending the source processes of Indian earthquakes. It has been possible mainly due to the installation of digital broadband and short period stations as a national network and detailed aftershock studies conducted for several earthquakes of M greater than or equal to6, Investigations of the seismogenic faults, including drilling, helium measurements and magneto-telluric surveys over the fault zones for some earthquakes have provided valuable inputs to characterize the scismogenesis of the Indian lithosphere, We discuss the significant results obtained from the seismological, geophysical and geological investigations for five recent moderate earthquake sequences (Uttarkashi 1991 and Chamoli 1999 in Garhwal Himalaya; Koyna 1967-1996, Latur 1993 and Jabalpur 1997 in the peninsular shield region). A better understanding of the causative faults and rupture processes involved in generating Indian earthquakes is obtained. Occurrence of Garhwal Himalayan earthquakes has been attributed to the significant concentration of stresses around the asperity/ramp on the detachment plane due to northward under-thrusting of the Indian lithosphere. The continued seismicity at the Koyna-Warna seismic zone and its triggering by reservoirs has been explained in terms of southward migration of seismicity from Koyna reservoir, high filling rate, duration of loading, Kaiser effect and nucleation process of moderate earthquakes. Seismological observations, geological evidences, drilling results and modelling of intra-plate stresses showed that occurrence of stable continental region earthquakes like Latur (1993) can be explained in terms of sudden movement along the pre-existing faults caused by a coupled force system consisting of topography, density heterogeneity and a NNE compression due to movement of the Indian plate. Further, a highly conductive low-velocity fluid-filled zone at 7-10 km depth beneath the focal zone of the Latur earthquake sequence, as suggested by magneto-tellurics study, low Bouguer gravity and observation of a Pc phase, will enhance stress concentration in the uppermost part of the crust, resulting in mechanical failure. Nevertheless, the nucleation of Jabalpur earthquake (1997) in the lower crust has been attributed to the sudden movement along the south Narmada fault due to the stress concentration around the 'rift pillows', Progress is made in understanding the source processes, crustal velocity structure and Q for some important tectonic regions of the Indian lithosphere and future directions have been identified. [References: 59]
机译：在理解印度地震的震源过程方面，20世纪的最后十年取得了很大进展。造成这种情况的主要原因可能是由于安装了数字宽带和短期站作为国家网络，并对M大于或等于6的几次M地震进行了详细的余震研究，包括地震勘探，钻探，氦测量和磁磁学研究。断层带上的某些地震的碲调查为表征印度岩石圈的地震形成提供了有价值的输入，我们讨论了从最近五次中等地震序列的地震，地球物理和地质调查中获得的重要结果（Uttarkashi 1991和Chamoli 1999在Garhwal喜马拉雅山; Koyna 1967-1996; Latur 1993和Jabalpur 1997（位于半岛盾构区域）。更好地了解了引发印度地震的原因性断裂和破裂过程。 Garhwal喜马拉雅地震的发生是由于印度岩石圈向北俯冲所致，在分离面上的凹凸不平处/斜坡附近应力集中很大。 Koyna-Warna地震带的持续地震活动及其受储层的触发作用，从Koyna水库向地震的南移，高填充率，加载持续时间，Kaiser效应和中地震成核过程方面进行了解释。地震观测，地质证据，钻探结果和板内应力模拟表明，稳定的大陆区域地震（如Latur（1993））的发生可以解释为由耦合力系统引起的沿既有断层的突然运动。地形，密度异质性和印度洋板块运动引起的NNE压缩。此外，如磁电研究，低布格重力和观测到的Pc相所暗示的那样，在拉图尔地震序列震源区以下7-10 km深度处的高导电性低速流体充满带将增强应力集中。在外壳的最上部，导致机械故障。尽管如此，下地壳的贾巴尔普尔地震（1997）的形核归因于由于“裂谷”周围的应力集中而沿南纳尔默达断层的突然运动。在了解震源过程，地壳速度结构方面取得了进展印度岩石圈一些重要构造区域的Q和Q值以及未来的方向已经确定。 [参考：59]

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