2D resistivity model around the rupture area of the 2011 Tohoku-oki earthquake (Mw 9.0)
2D resistivity model around the rupture area of the 2011 Tohoku-oki earthquake (Mw 9.0)
复制标题
2011年东北冲地震破裂区周围的二维电阻率模型（Mw 9.0）
DOI：
10.1186/s40623-023-01828-1
复制
发表时间：
2023
期刊：
影响因子：
--
通讯作者：
M. Yamano
中科院分区：
文献类型：
--
作者：
H. Ichihara;T. Kasaya;K. Baba;T. Goto;M. Yamano
2011年东北地震(Mw9.0)的特点是在板块界面最浅的部分发生了巨大的断层滑动，那里的断层行为被认为是无地震的。在这项研究中，我们基于海底电磁测量，模拟了滑移区的二维电阻率分布，以了解控制断层破裂过程的板块界面周围的物理性质。最优的二维电阻率模型显示，在最浅的板块界面附近有一个传导区，在那里观察到了巨大的同震滑动，而断层破裂成核的较深板块界面的电阻率相对较高。最浅的板块界面具有较高的孔隙海水含量，而较深的界面被解释为干燥区。这些发现与假设一致，即当断层破裂传播到潮湿、粘土丰富的最浅板区时，无地震摩擦条件转变为加强断层破裂的条件。最优电阻率模型还揭示了太平洋板块外隆起区下方的导电区。这一发现支持了水合洋壳的存在，它为俯冲带提供了水，包括向巨大的断层滑移区提供了水。图形摘要
The 2011 Tohoku-oki earthquake ( M w 9.0) was characterized by a huge fault slip on the shallowest part of the plate interface, where fault behavior had been believed to be aseismic. In this study, we modeled the two-dimensional resistivity distribution across the slip area based on ocean-bottom electromagnetic measurements to understand the physical properties around the plate interface controlling fault rupture processes. The optimal 2D resistivity model showed a conductive area around the shallowest plate interface where the huge coseismic slip was observed, whereas the deeper plate interface where the fault rupture was nucleated was relatively more resistive. The shallowest plate interface was interpreted to have a high pore seawater fraction, whereas the deeper interface was interpreted as a dry area. These findings are consistent with the hypothesis that aseismic frictional conditions changed to conditions enhancing fault rupture when the rupture propagated to the wet, clay-rich shallowest plate area. The optimal resistivity model also revealed a conductive area under the outer-rise area of the Pacific Plate. This finding supports the existence of a hydrated oceanic crust that supplied aqueous water to the subduction zone, including to the huge fault slip area. Graphical Abstract
影响因子：
3.5
作者：
Wessel, P.;Luis, J. F.;Tian, D.
通讯作者：
Tian, D.
影响因子：
64.8
作者：
Chesley, Christine;Naif, Samer;Bassett, Dan
通讯作者：
Bassett, Dan