On moment-length scaling of large strike slip earthquakes and the strength of faults

Abstract

Several large strike slip earthquakes have occured in various tectonic settings in the past 5 years, adding well documented data to the global collection of moment and length estimates for such earthquakes. Based on this augmented dataset, we reexamine the controversial issue of scaling of seismic moment with length of rupture. We find that the global dataset of large strike-slip earthquakes follows a bi-modal distribution. Most oceanic and/or intraplate strike-slip earthquakes have stress drops that are ∼5 times larger than interplate continental ones. When distinguishing these two classes, the scaling is compatible with that predicted by simple dislocation theory.