On behaviour and scaling of small repeating earthquakes in rate and state fault models
On behaviour and scaling of small repeating earthquakes in rate and state fault models
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关于速率和状态断层模型中小重复地震的行为和尺度
DOI：
10.1093/gji/ggz270
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发表时间：
2019
影响因子：
2.8
通讯作者：
Lapusta, Nadia
中科院分区：
文献类型：
--
作者：
Chen, Ting;Lapusta, Nadia
由于小重复地震的地震数据丰富，构建能够解释相关观测各个方面的动力学模型非常重要。在这项工作中，我们研究了受速率和状态相关摩擦定律控制的断层上的小重复地震。地震发生在速度减弱的区域，周围环绕着更大的速度增强区域。整个断层承受着长期的构造荷载。在先前的研究中，具有圆形斑块以及速率和状态相关摩擦定律的老化形式的模型已被证明可以再现小重复地震的复发时间与地震矩的比例。在这里，我们研究了不同场景下相关模型中小重复地震的行为，包括速率和状态相关摩擦定律中状态演化方程的几种形式、矩形速度弱化斑块几何形状、惯性效应的准动态与完全动态表示以及 2-D 与 3-D 模拟。我们发现这些不同场景的重现时间和地震矩之间的模拟尺度相似，但确实存在差异。我们提出了小重复地震的复发时间和地震矩之间的缩放比例的理论考虑。对于小于或等于完全成核尺寸的补片半径，缩放可以通过地震与地震滑移比随震级的增加来解释。对于大于完整成核尺寸的补片半径，缩放比例可以通过模型来解释，其中重现时间由地震成核时间决定，而地震成核时间又由地震滑移穿透完整成核尺寸的距离进入补片的时间决定。获得的理论见解用于找到断层属性的组合，使模型能够拟合观测到的地震矩和重现时间的尺度和范围。
With abundant seismic data for small repeating earthquakes, it is important to construct a dynamic model that can explain various aspects of related observations. In this work, we study small repeating earthquakes on a fault governed by rate- and state-dependent friction laws. The earthquakes occur on a velocity-weakening patch surrounded by a much larger velocity-strengthening region. The whole fault is subject to long-term tectonic loading. The model with a circular patch and the aging form of rate- and state-dependent friction laws has been shown to reproduce the scaling of recurrence time versus seismic moment for small repeating earthquakes in a previous study. Here we investigate the behaviour of small repeating earthquakes in related models under different scenarios, including several forms of the state evolution equations in rate- and state-dependent friction laws, rectangular velocity-weakening patch geometries, quasi-dynamic versus fully dynamic representation of inertial effects and 2-D versus 3-D simulations. We find that the simulated scalings between the recurrence time and seismic moment for these different scenarios is similar while differences do exist. We propose a theoretical consideration for the scaling between the recurrence time and seismic moment of small repeating earthquakes. For patch radii smaller than or comparable to the full nucleation size, the scaling is explained by the increase of seismic to aseismic slip ratio with magnitude. For patch radii larger than the full nucleation size, the scaling is explained by the model in which the recurrence time is determined by the earthquake nucleation time, which is in turn determined by the time for aseismic slip to penetrate the distance of the full nucleation size into the patch. The obtained theoretical insight is used to find the combinations of fault properties that allow the model to fit the observed scaling and range of the seismic moment and recurrence time.
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圣安德烈亚斯断层带的科学钻探
DOI：
10.1029/2010eo220001
发表时间：
2010
期刊：
Eos, Transactions American Geophysical Union
影响因子：
--
作者：
M. Zoback;S. Hickman;W. Ellsworth
通讯作者：
W. Ellsworth
影响因子：
2.3
作者：
N. Kato;Tomowo Hirasawa
通讯作者：
N. Kato;Tomowo Hirasawa
圣安德烈亚斯断层深度观测站圣安地列斯断层带内的地球物理特性及其与岩石特性和断层带结构的关系
影响因子：
--
作者：
T. Jeppson;K. Bradbury;James P. Evans
通讯作者：
James P. Evans
DOI：
10.1029/gm037
发表时间：
1986
期刊：
--
影响因子：
--
作者：
Shamita Das;J. Boatwright;C. Scholz
通讯作者：
Shamita Das;J. Boatwright;C. Scholz
影响因子：
5.2
作者：
Kato, N;Tullis, TE
通讯作者：
Tullis, TE