IRANIAN JOURNAL OF SCIENCE AND TECHNOLOGY-TRANSACTIONS OF CIVIL ENGINEERING, cilt.46, sa.2, ss.1037-1047, 2022 (SCI-Expanded, Scopus)
The near-surface seismodynamic parameters in the upper crust can be a useful tool for seismic risk and identifying the distribution of seismic anisotropy with tectonic structures. The determination of these parameters is crucial and necessary for determining seismic risk and understanding seismic anisotropy. For this purpose, six seismic stations with a total of 934 earthquakes were used in eastern Anatolia. In this paper, near the upper crust of the middle and eastern Anatolia was investigated by using regional seismodynamic tomography of Pg- and Sg-wave attenuation coefficients (P alpha and S alpha) and initial amplitudes parameters (P-A0 and S-A0) for six distinct regions. The attenuation coefficients (P-alpha-S-alpha and P-A0-S-A0) and initial amplitude (P-A0-S-A0) parameters of the regional Pg and Sg waves were mapped to supply insight into the upper crustal seismic risk and seismic anisotropy. The 3-D tomographic results show that, in general, alpha and A(0) values are considerably smaller for the west of the study area than those found in other tectonic areas. The comparison of two-dimensional seismodynamic parameters (P-A0-S-A0, P alpha-S alpha) reveals the presence of four different seismodynamic zones. The 3-D tomographic results clearly show that compressional effect is between the Arabian block and Anatolia block along the big fault branches such as the East Anatolia Fault Zone (EAFZ), North-East Anatolian Fault Zone (NEAFZ) and Malatya Ovacik Fault Zone (MOFZ). Furthermore, one of the most important findings of this study is that clustering and sudden changes in P-A0-S-A0 values are clearly visible in Karliova Triple Junction (KTJ) structure and its surroundings. This study results supported the complex tectonic structures northward movement of the Arabian plate and lithospheric compression of central and eastern Turkey.