GPS derived finite source mechanism of the 30 October 2020 Samos earthquake, Mw = 6.9, in the Aegean extensional region

Abstract

A submarine area close to the Turkish and Greek border between the cities of Samos-Greece and Seferihisar-Turkey has been shaked on October 30, 2020 by a Mw= 6.9 earthquake. In this study, the finite source mechanism of the Samos earthquake was investigated using geodetic methods and the coseismic behavior of the earthquake was modeled. The observed coseismic displacements at 62 sites were inverted for the fault geometry and the slips. The mainshock did not generate an on-land surface rupture. However, the uniform slip modeling shows a finite source of 43.1 km long and 16 km wide rupture, which slips 1.42 m along a north dipping normal fault extending from the Aegean Sea floor to a depth down to ~13 km. While the uniform slip model is consistent with the seismological solutions and provides a sufficient fit to the far field coseismic offsets, a distributed slip model is necessary to account for the near field coseismic displacements.