Geodetic Source Modeling of the 2019 Mw 6.3 Durres, Albania, Earthquake: Partial Rupture of a Blind Reverse Fault

We address geometric and kinematic properties of the M-w 6.3 26 November 2019 Durres earthquake, the strongest earthquake in Albania in the past 40 years. Using coseismic surface displacements from Sentinel-1 Differential Interferometric Synthetic Aperture Radar (DInSAR) and nearby Global Navigational Satellite System (GNSS) stations, we invert for the geometry and slip of the causative fault. We find that both a steep SW-dipping fault (dip 71 degrees) and a shallow NE-dipping fault (dip 15 degrees) can fit the data equally well. However, the slip on the SW-dipping fault occurs at depths 11-23 km, similar to the depths of the mainshock and aftershock seismicity, and thus, we prefer that model. The location of our preferred fault plane correlates with the mapped SW-dipping backthrust, the Vore fault. The fault rupture did not reach the surface, which implies that an updip stress propagation onto the unruptured shallow portion of the Vore fault and its secondary structures pose an increased seismic hazard for cities in Albania, including the capital, Tirana.