据介绍，研究机械扰动对颗粒系统的影响对于理解土壤稳定性、雪崩和地震至关重要。
该课题组人员研究了一个颗粒系统作为断层泥的实验室代理。当受到缓慢剪切时，颗粒材料通常在达到稳定状态之前表现出应力过冲。研究发现，短地震脉冲可以使流动的颗粒系统恢复到稳态状态，从而使应力过冲得到恢复。
这一特征被用来确定在扰动脉冲后不同外加应力下颗粒系统的稳定性，以及颗粒系统失效时的动态特性。研究人员利用分析老化—恢复模型来描述过冲响应，结果表明实验室推导的理论框架可以定量解释，由地震波触发的两次断层滑动事件的数据。
附：英文原文
Title: Perturbation-induced granular fluidization as a model for remote earthquake triggering
Author: Kasra Farain, Daniel Bonn
Issue&Volume: 2024-04-17
Abstract: Studying the effect of mechanical perturbations on granular systems is crucial for understanding soil stability, avalanches, and earthquakes. We investigate a granular system as a laboratory proxy for fault gouge. When subjected to a slow shear, granular materials typically exhibit a stress overshoot before reaching a steady state. We find that short seismic pulses can reset a granular system flowing in steady state so that the stress overshoot is regenerated. This feature is shown to determine the stability of the granular system under different applied stresses in the wake of a perturbation pulse and the resulting dynamics when it fails. Using an analytical aging-rejuvenation model for describing the overshoot response, we show that our laboratory-derived theoretical framework can quantitatively explain data from two fault slip events triggered by seismic waves.
DOI: adi7302
Source: https://www.science.org/doi/10.1126/sciadv.adi7302