Code: Co-Seismic Surface Deformation Associated with the 20 April 2026 Mw 7.5 Earthquake East of Honshu, Japan

This repository contains the Python codes used to determine the consensus focal mechanism and model co-seismic surface deformation associated with the 20 April 2026 Mw 7.5 earthquake east of Honshu, Japan. The scripts include: (1) decomposition of the surface deformation field into volumetric, north, east, and northeast components; (2) modeling and visualization of vertical and horizontal co-seismic displacement fields over an Earth relief basemap; (3) computation of the principal horizontal strain field; (4) moment tensor computation and generation of the focal mechanism (beachball) diagram together with the 3D P-wave radiation pattern for the consensus mechanism; and (5) quantification of geometric similarity among focal mechanism solutions from nine international agencies using Kagan rotation angles, with hierarchical clustering visualization (dendrogram and heatmap). These codes constitute the computational support for the companion paper and allow reproduction of the consensus focal mechanism analysis and co-seismic surface deformation characterization presented therein.