Qc, Qp, Qs, Qi, and Qsc attenuation parameters in the southern part of Georgia

Georgia is located in the Caucasus between The black and the Caspian seas and is surrounded by the Greater and Lesser Caucasus. Among the seismic areas of Georgia, the volcanic upland of Javakheti situated in the south of Georgia is notable for its high level of seismicity where three large earthquakes with M6 occurred in the last century. The main goal of the study is to investigate the attenuation properties of the lithosphere in the region using a hundred and twenty local earthquakes in 2008-2020  recorded at five seismic stations equipped with broadband Guralp CMG40T and Trillium 40  seismometers. Earthquake magnitudes varied from 1.5 to 4.1; epicentral distances and depth were smaller than 60 km and 19 km, respectively. The quality factors of coda waves Qc and direct P, S waves Qp, and Qs have been estimated using the single back-scattering model and the extended coda normalization methods, respectively. Wennerberg’s approach has been used to estimate intrinsic Qi and scattering Qs attenuation parameters. The Q  values were fitted to a  power-law, of form Q (f)= Q0 (f)n, where Q0 is the quality factor at 1Hz and n is the frequency relation parameter, which depends on the heterogeneity of the medium. The obtained values of Qc, Qp, Qs, Qi, and Qsc show the frequency-dependent character in the frequency range of 1.5-24 Hz and are expressed as: Qc = (47.6±3.8)(1.034±0.048),  Qp = (17.4±2.3)