Faulting and its surrounding topographic undulations in analogue models revealed by optical measurements and image correlation techniques (Invited)

In recent decades, substantial efforts have been paid to measure analogue model results digitally. One of the most successful techniques may be digital image correlation (DIC) applied for time-lapse photography of model surfaces. DIC has been used to detect faulting by calculating strain distributions from velocity differences in neighboring areas in experimental material. With this technique, the dynamic process of fault development in thrust-belts has been visualized. Detailed internal structures of a shear zone in analogue models have also been revealed by DIC that suggests a life of a fault can be classified into three stages. The resultant geometry of the shear zone in granular materials can be correlated to typical shear zone structures in nature that consist of a damage zone and a fault core. DIC has also been applied to surface process during deformation, such as slope failures, and the results propose a mechanical model of submarine slides. Topography has also been measured during experiments with a laser scanner or optical sensors of a stereo-pair. The progressive development of the surface topography can be used for stability assessment in actively deforming regions.