Aftershock Moment Tensor Scattering

Abstract Coseismic rotations of principal stress axes can provide insights into the strength crust, but it is unclear how common this phenomenon is. We use a nearest‐neighbor clustering algorithm to identify earthquake sequences in global ISC‐GEM catalog and regional Southern California catalog. Using an inner‐product‐based pairwise measure moment tensor similarity, we demonstrate that, both catalogs, aftershocks are less similar their respective mainshocks than foreshocks are. interpret effect, which call scattering, as evidence for widespread coseismic rotations. Moment scattering observable broad range mainshock magnitudes catalogs. further that mainshock‐aftershock similarity recovers logarithmically pre‐mainshock levels on decadal timescales. conclude generally feature seismic may be useful future work discriminate between models crustal strength.