Mikroslip

Mikroslip is a term used in friction science and seismology to describe small-scale slip events that occur at the interface between sliding bodies under shear stress, typically preceding or accompanying larger slip events. The term combines “micro” with “slip” to signal a scale well below macro-scale earthquakes or full-release slips. In laboratory and field settings, mikroslips are detected as brief, low-displacement movements accompanied by changes in frictional resistance.

Mechanisms underlying mikroslip include the nucleation of slip at microscopic surface features, such as asperities, and the process of stick-slip behavior driven by rate- and state-dependent friction. Localized weakening, pressure changes within the contact, thermal effects, and the evolution of contact area can cause rapid, small slips that release part of the accumulated shear. Mikroslips can either remain contained within a contact region or propagate into larger events under certain conditions.

Measurement and evidence of mikroslip come from high-resolution laboratory friction experiments, including rock friction tests with gouge layers, atomic force microscopy, and precision shear measurements. In seismology, microseismic activity can reveal sequences of small, rapid slips that may accompany or foreshadow larger ruptures, though distinguishing mikroslips from other fault processes requires careful analysis.

Modeling and theory often employ rate-and-state friction frameworks, which can reproduce intermittent slip behavior and the interplay between slip, contact aging, and thermal effects. Mikroslips are relevant for understanding fault healing, frictional aging, and energy dissipation in interfaces, as well as for engineering tribology where small-scale slips influence wear and noise.

See also: friction, stick-slip, rate-and-state friction, tribology.