Characterization of Fault Roughness at Various Scales: Implications of Three-Dimensional High Resolution Topography Measurements

TL;DR

This study uses high-resolution 3D LIDAR measurements to analyze the scaling and anisotropy of fault surface roughness, providing insights into fault mechanics and earthquake processes.

Contribution

It introduces a detailed analysis of fault surface roughness at multiple scales using advanced 3D topography measurements, highlighting anisotropic features.

Findings

Fault surfaces exhibit scale-dependent roughness properties.

Anisotropy in fault roughness correlates with fault type.

High-resolution data improves understanding of fault mechanics.

Abstract

Accurate description of the topography of active faults surfaces represents an important geophysical issue because this topography is strongly related to the stress distribution along fault planes, and therefore to processes implicated in earthquake nucleation, propagation, and arrest. With the recent development of Light Detection And Ranging (LIDAR) apparatus, it is now possible to measure accurately the 3D topography of rough surfaces with a comparable resolution in all directions, both at field and laboratory scales. In the present study, we have investigated the scaling properties including possible anisotropy properties of several outcrops of two natural fault surfaces (Vuache strike-slip fault, France, and Magnola normal fault, Italy) in limestones.