Laboratory Experiments on Rock Friction Focused on Understanding Earthquake Mechanics

EAR-0003543特里·E·图利斯和大卫·L·戈德斯比摘要研究人员提议进行一项系统研究，以了解岩石摩擦中识别的各种效应的基本过程。他们将进行实验，以了解是什么过程导致了单个摩擦接触、多个接触以及刨削中接触之间的相互作用的时间依赖性，特别是在刨削内的滑动面上。目的是了解观察者在地震周期的大部分时间里可能会在断层上发现的摩擦行为。问题是，众所周知的在实验室中确定的摩擦力的经验率和状态摩擦力描述，目前不能有任何信心地扩展到地球上的断层，因为我们不了解这种行为背后的基本过程。为了理解地震成核，一个基本的要求是理解时间相关性，这种时间相关性允许断层在动态事件之间加强，并导致它们随着滑动的加速而减弱。研究人员将进行一系列微压痕和摩擦实验，旨在通过流体化学和温度的变化来区分最可能的解释类别，并通过密集的微观结构研究来区分。

EAR-0003543 Terry E. Tullis and David L. Goldsby ABSTRACT The investigators propose a systematic study to understand the fundamental processes responsible for the various effects recognized in rock friction. They will conduct experiments aimed at understanding what processes are responsible for the time dependence of interaction between single frictional contacts, multiple contacts, and contacts in gouge, especially on slip surfaces within gouge. The purpose is to understand the frictional behavior observers might expect to find on faults during most parts of the earthquake cycle. The problem is that the well-known empirical rate and state friction description of friction, as determined in the laboratory, cannot presently be extended to faults in the Earth with any confidence, because we do not understand the fundamental processes underlying the behavior. To understand earthquake nucleation it is a fundamental requirement to understand the time dependence that allows faults to strengthen between dynamic events and causes them to weaken as slip accelerates. The investigators will conduct a series of microindentation and friction experiments designed to differentiate between the most likely classes of explanations by variation of fluid chemistry and temperature and through an intensive microstructural study.