Rate and state frictional and healing behavior of carbonate fault gouge explained using microphysical model
Rate and state frictional and healing behavior of carbonate fault gouge explained using microphysical model
复制标题
用微物理模型解释碳酸盐岩断层泥的速率和状态摩擦及愈合行为
DOI：
10.1002/2016jb013470
复制
发表时间：
2016-12-01
影响因子：
3.9
通讯作者：
Spiers, Christopher J.
中科院分区：
文献类型：
--
作者：
Chen, Jianye;Spiers, Christopher J.
经典的速率-状态摩擦（RSF）定律被广泛应用于地震动力学建模，但通常使用经验确定的参数，很少或没有知识，或定量的帐户，控制物理机制。在这里，一个基于机制的微观物理模型来描述碳酸盐岩断层泥的摩擦行为，假设在实验室实验中看到的摩擦行为是由速率强化粒间滑动与接触蠕变压力溶液的竞争过程控制。通过求解控制方程，来自运动学和能量/熵平衡的考虑，并采用率强化晶界摩擦加标准蠕变方程的压力解决方案的微观物理模型，我们模拟典型的实验室摩擦测试，即“速度步进”和“滑动保持滑动”测试序列，速度的历史和环境条件在以前的实验。建模结果捕获了实验结果中看到的所有主要特征和趋势，包括观察到的行为的稳态和瞬态方面，具有合理的定量一致性。据我们所知，我们的模型是第一个基于机制的模型，它可以在微观结构上验证过程和状态变量方面再现类似RSF的行为。由于它是基于微物理，我们相信，我们的建模方法可以提供一个改进的框架外推摩擦数据的自然条件。
Classical rate-and-state friction (RSF) laws are widely applied in modeling earthquake dynamics but generally using empirically determined parameters with little or no knowledge of, or quantitative account for, the controlling physical mechanisms. Here a mechanism-based microphysical model is developed for describing the frictional behavior of carbonate fault gouge, assuming that the frictional behavior seen in lab experiments is controlled by competing processes of rate-strengthening intergranular sliding versus contact creep by pressure solution. By solving the controlling equations, derived from kinematic and energy/entropy balance considerations, and employing a microphysical model for rate-strengthening grain boundary friction plus standard creep equations for pressure solution, we simulate typical lab-frictional tests, namely, "velocity stepping" and "slide-hold-slide" test sequences, for velocity histories and environmental conditions employed in previous experiments. The modeling results capture all of the main features and trends seen in the experimental results, including both steady state and transient aspects of the observed behavior, with reasonable quantitative agreement. To our knowledge, ours is the first mechanism-based model that can reproduce RSF-like behavior in terms of microstructurally verifiable processes and state variables. Since it is microphysically based, we believe that our modeling approach can provide an improved framework for extrapolating friction data to natural conditions.