Present-day kinematics in the Eastern Mediterranean and Caucasus from dense GPS observations

The Eastern Mediterranean and Caucasus are located among the Eurasian, African and Arabian plates, and tectonic activities are very complex. In this paper, the kinematics and strain distribution in these regions are determined and investigated from dense GPS observations with over 1000 stations and longer observations. The elastic block model is used to constrain present-day plate motions and crustal deformation. The relative Euler vectors between the Nubian, Arabian, Caucasus, Anatolian and Central Iranian plates are estimated. The Arabian-Eurasia, Anatolian-Eurasia, Nubian-Eurasia, Caucasus-Eurasia and Central Iranian Euler vectors are 0.584 ± 0.1 Myr−1, 0.825 ± 0.064 Myr−1, 0.35 ± 0.175 Myr−1, 0.85 ± 0.086 Myr−1 and 0.126 ± 0.016 Myr−1. The strain rate in the East Mediterranean and Caucasus has been estimated from the GPS velocity field. The results show that the thrust dominated areas, the eastern Mediterranean-Middle East-Caucasus and Zagros have negative dilatation and the western Anatolia region has positive 2D dilatation rate with significant rotation. The west Anatolian shows the extension in NW-SE with about 150-199 nstrain/yr in the W-E direction. The Central Anatolia shows compression rate below 50 nstrain/yr and extensional strain rate adjacent to East Anatolian Fault and Dead Sea Fault is about 0-100 nstrain/yr. The contraction strain rate is higher in Zagros and Caucasus between 100-150 nstrain/yr and contraction orientation is along the NE-SW direction in Caucasus. The north part of Iran shows less contraction rate below 50 nstrain/yr but North-East Zagros Mountains, Tabriz fault and Chalderan fault show extensional rate between 50-110 nstrain/yr and principal axes rotation in the N-S direction. The maximum contraction observed in the Kopek Dag is about 100-194 nstrain/yr and orientated in the NE-SW direction. East Zagros Mountain and Makran subduction zone have a large clockwise rotation with 70-85 nradian and principal axes remains mostly along the N-S direction. The observed extension is along N-S by about 0-100 nstrain/yr with counter clockwise rotation in Dead Sea Fault. The Sinai block shows shortening rate in the range of 0-100 nstrain/yr.