Ufuk Aydın
Abstract
In this paper have been conducted an analysis of seismic velocity waves to determine poisson’ s ratio of the crust and its implications for the eastern Anatılian and east black sea bounded. The Pg and Sg wave arrival times of 349 data recorded by three stations was used to examine the geotectonics of the study area. The Pg and S ave velocity were determined as 5.506 km/s and 3.146 km/s, respectively for the whole study area. The Vp/Vs ratios were calculated as 1.72- 1.75 with an average of 1.74. Poisson’ s ratio (σ=0.204) have been obtained for the whole study area. The greatest Poisons’ ratio values were observed for KTUT, while the smalests was observed in the ERZN stations. The highest Poisson’s ratio values were obtained in the north part, while the lowest σ values were obtained in the south of the study area. The lateral seismic velocity variations demonstrated different crustal thickness and inhomogeneous compressional activation of north and east Anatolian fault zone that were developed by the thrust of the North Anadolu Fault Zone (NAFZ) and Bitlis Zagros Suture (BZS). The obtained lateral seismic velocity and Poission’ s ratio changes indicate the lithospheric compression or strain effects of theEast Anatolia Fault Zone (EAFZ) and Bitlis Zagros Suture Zone (BZSZ) in the near crust and the sub-crust tectonic disturbance. This study shows that tectonic structures and lithospheric inhomogeneity structures can be defined by the dynamic properties such as Poission’ s ratio of the near upper Earth crust.
Keywords
Upper crust, Tectonic structures, Seismic velocity, Poisson’s ratio (σ), Tectonic heterogeneity.
