University of Tehran Press Journal of the Earth and Space Physics 2538-371X 31 1 2005 03 21 - - 10870 FA Journal Article Near-field data obtained from the main shock of May 28, 2004 Baladeh-Kojour earthquake, with Mw = 6.2 is used to determine the frequency dependence of direct shear wave quality factor Q?, in the range of 1 to 32 Hz. Based on the regression analysis, the following equation is proposed: Q? = 90f0.74 High attenuation factor and frequency dependence of quality factor for shear waves imply the high seismicity of the region and agrees well with similar studies in other seismically active regions such as Greece, Japan, India, etc. Near-field data obtained from the main shock of May 28, 2004 Baladeh-Kojour earthquake, with Mw = 6.2 is used to determine the frequency dependence of direct shear wave quality factor Q?, in the range of 1 to 32 Hz. Based on the regression analysis, the following equation is proposed: Q? = 90f0.74 High attenuation factor and frequency dependence of quality factor for shear waves imply the high seismicity of the region and agrees well with similar studies in other seismically active regions such as Greece, Japan, India, etc. https://jesphys.ut.ac.ir/article_10870_fb9d433088a21464e7d634c4e190b31a.pdf