Mapping of Interplate Coupling in the Kamchatka Subduction Zone from Variations in the Earthquake Size Distribution

Abstract

The geometry of supposed coupling zones in the Kamchatka subduction zone is determined by the earthquake size distribution based on ealier revealed relationship between its shape and rate of inelastic deformations. In the areas of higher aseismic slip, a break of linearity in earthquake size distribution is observed owing to the deficit of large earthquakes. Zones of higher coupling between the oceanic and continental plates are characterized by an excess of large earthquakes and an inverse bend in the earthquake size distribution. The mapping results of the bend value agree with the coupling zones distinguished from satellite geodetic data and inversion of marigrams.