Dual Seismic Migration Velocities in Seismic Swarms
Dual Seismic Migration Velocities in Seismic Swarms
复制标题
地震群中的双地震偏移速度
DOI：
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发表时间：
2020
影响因子：
5.2
通讯作者：
L. de Barros
中科院分区：
文献类型：
--
作者：
P. Dublanchet;L. de Barros
流体诱发的地震序列通常表现为扩大的地震群，激活了一个特定的断层。最近对科林斯裂谷群的分析揭示了一种双重迁移模式，即全球缓慢扩张（m day - 1）和快速迁移（km day - 1）。这种群体通常被解释为流体扩散，忽略了静态、动态或地震触发的可能性以及快速迁移的存在。在这里，我们提出了一种新的地震群模型，其中地震是由流体渗透的爬行断层上的凹凸不平的破坏构成的。为此，我们沿着一维界面耦合了速率和状态摩擦、非线性扩散率和弹性。这个模型再现了在真实群体中观察到的双重迁移速度。研究表明，运移速度随平均压力线性增加，而不像传统观点那样依赖于水力扩散系数。
Fluid‐induced earthquake sequences generally appear as expanding swarms activating a particular fault. The recent analysis of a swarm in the Corinth rift has revealed a dual migration pattern, with a global slow expansion (m day−1) and episodes of rapid migration (km day−1). Such swarms are generally interpreted as fluid diffusion, which ignores the possibility of static, dynamic, or aseismic triggering and the existence of rapid migration. Here, we propose a new model for such swarms, where earthquakes consist in the failure of asperities on a creeping fault infiltrated by fluid. For that, we couple rate‐and‐state friction, nonlinear diffusivity, and elasticity along a 1D interface. This model reproduces the dual migration speeds observed in real swarms. We show that migration speeds increase linearly with the mean pressurization and are not dependent on the hydraulic diffusivity, as traditionally suggested.
影响因子：
56.9
作者：
Bhattacharya, Pathikrit;Viesca, Robert C.
通讯作者：
Viesca, Robert C.