Complex Shallow Unilateral Rupture of the 2025 M w 7.0 Hubbard Glacier Earthquake Terminated by a Restraining Bend on the Connector Fault

Abstract Despite decades of study, the detailed geometry of the Connector fault at the Alaska–Canada border remains poorly constrained. We investigate the rupture complexity and directivity of the 6 December 2025, M w 7.0 Hubbard Glacier earthquake using hypocenter relocations, moment tensor inversions of the mainshock and aftershocks, and finite‐fault modeling. We model seismological data using bootstrap and Bayesian‐based probabilistic inversion. Observations indicate that the mainshock rupture was complex, nucleated with a right‐lateral strike‐slip mechanism and propagating northwestward, ultimately terminating in a restraining bend. Source inversion of the mainshock reveals shallow right‐lateral oblique‐slip on a fault striking 303° and dipping 63° NE. Relocated aftershocks delineate an ∼60 km‐long seismic zone characterized by strike‐slip mechanisms along the ruptured area and reverse/thrust at the left stepover of the fault. Our results provide a detailed mechanism for a buried Connector structure and highlight the role of fault bends in controlling rupture evolution.