02.03.2017 and 24.04.2018 Samsat (Adiyaman) Earthquakes and Their Importance in Regional Seismotectonics

Abstract

In this study, Synthetic Aperture Radar Interferometry (InSAR) method is used together with field observations to determine whether surface deformations occur in the region after the 5,5 Mw (AFAD) Samsat Earthquake occurred at a distance of 2.5 km from the Samsat district of Adiyaman province on 2 March 2017. We attempted to determine the deformation of the interferogram created by analyzing two Synthetic Aperture Radar (SAR) images of the Sentinel-1A fit before and after the earthquake. As a result of the evaluation of the interferogram, a surface deformation of about 2.5 cm in the satellite view direction/Line of Sight (LoS) was observed in the region. This deformation is mostly concentrated in the northeast of Samsat town. As a result of the detailed field investigations made immediately after the earthquake in the region, no surface rupture occurred but surface deformations in the form of local and discontinous fissures developed in some areas. It is understood that the Earthquake developed on a fault passing through about 5 Km North of Samsat and named as Samsat Fault by TPAO. It appears that more than 400 aftershocks following the main shock in the region concentrate roughly on a N40-50W lineament. It is noteworthy that in the observations made in the field, the distribution of the damage has also developed along this line in particular.