Abstract

This paper is a brief review of the main recent results obtained by studying fault slip processes. The published hypotheses and data are analyzed within the approach proposed by Panin, according to which the subsurface is considered as a multilevel hierarchically organized system where all processes evolve consistently at the nano-, micro-, meso- and macroscale levels. The review focuses on the hierarchy of structures that, according to modern concepts, form the seismogenic fault slip zone. The relationship of the structures with the mechanical characteristics of localized slip surfaces and microcontacts determining the slip dynamics of fault zones at the macrolevel is discussed. It is shown that the evolution of the contact properties of filler particles in the slip zone determines not only the occurrence of instability, but also the ability of a fault to recover strength with time. The simplest scheme of the hierarchy of macroscopic asperities is described to support the important principle that the initiation, evolution and arrest of a seismogenic fault depend on the size and relative position of regions with different dynamics of frictional characteristics during slip. The performed analysis of the results of field observations shows that because of the insufficient accuracy of observations and the ambiguous interpretation of the inverse problem solution, it is impossible to correctly identify fault segments with the velocity weakening property. The size and location of these zones can be more accurately determined from the analysis of records of high-frequency oscillations in the vicinity of an earthquake rupture. The basic principles of physical mesomechanics provide a good basis for the interpretation of such results.

中文翻译：

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震源物理细观力学

摘要

本文简要回顾了最近通过研究断层滑动过程获得的主要结果。已发表的假设和数据在 Panin 提出的方法中进行了分析，根据该方法，地下被认为是一个多层次的分层组织系统，其中所有过程都在纳米、微米、中观和宏观尺度上一致地发展。综述的重点是根据现代概念形成发震断层滑动带的结构层次。讨论了结构与局部滑移面和微接触的力学特性之间的关系，这些微接触决定了宏观层面断层带的滑移动力学。结果表明，滑移区填料颗粒接触性能的演变不仅决定了不稳定性的发生，以及故障随时间恢复强度的能力。描述了最简单的宏观粗糙度等级方案，以支持一个重要原理，即发震断层的起始、演化和停止取决于滑动过程中具有不同摩擦特性动力学的区域的大小和相对位置。对现场观测结果的分析表明，由于观测精度不够，反问题解的解释不明确，无法正确识别具有速度减弱特性的断层段。通过对地震破裂附近高频振荡记录的分析，可以更准确地确定这些区域的大小和位置。