A statistical analysis of stick-slip experiments for bridging the scale gap between natural and lab earthquakes

In natural earthquakes (over km scales), slip displacement D is scaled with fault length L (Scholz, 1982). Laboratory stick-slip experiments have been thought to be analogue of seismic phenomena, but we find that they deviate from the L-D scaling using experimental data from 16 published papers. Namely the experimental data tends to have larger slip displacement than extension of the natural earthquake scaling. Here, we perform correlation analyses to investigate parameters governing the slip displacement D. The analyses imply that the slip displacement D is controlled by the characteristic time of inertia (which corresponds to the period of harmonic oscillation) independently of spatial scale, for experiments with artificial gouges.