caa a22 4500 463172183 CHVBK 20180406164816.0 cr unu---uuuuu 170326e20070701xx s 000 0 eng 10.1007/s10950-007-9057-z doi (NATIONALLICENCE)springer-10.1007/s10950-007-9057-z Attenuation of P, S, and coda waves in Koyna region, India [Elektronische Daten] [Babita Sharma, S. Teotia, Dinesh Kumar] The attenuation properties of the crust in the Koyna region of the Indian shield have been investigated using 164 seismograms from 37 local earthquakes that occurred in the region. The extended coda normalization method has been used to estimate the quality factors for P waves $$ {\left( {Q_{\alpha } } \right)} $$ and S waves $$ {\left( {Q_{\beta } } \right)} $$ , and the single back-scattering model has been used to determine the quality factor for coda waves (Q c). The earthquakes used in the present study have the focal depth in the range of 1-9km, and the epicentral distance vary from 11 to 55km. The values of $$ Q_{\alpha } , $$ $$ {\left( {Q_{\beta } } \right)} $$ and Q c show a dependence on frequency in the Koyna region. The average frequency dependent relationships (Q = Q 0 f n) estimated for the region are $$ Q_{\alpha } = {\left( {59 \pm 1} \right)}f^{{{\left( {1.04 \pm .04} \right)}}} $$ , $$ Q_{\beta } = {\left( {71 \pm 1} \right)}f^{{{\left( {1.32 \pm .08} \right)}}} $$ and $$ Q_{c} = {\left( {117 \pm 2} \right)}f^{{{\left( {0.97 \pm .07} \right)}}} $$ . The ratio $$ {Q_{\beta } } \mathord{\left/ {\vphantom {{Q_{\beta } } {Q_{\alpha } }}} \right. \kern-\nulldelimiterspace} {Q_{\alpha } } $$ is found to be greater than one for the frequency range considered here (1.5-18Hz). This ratio, along with the frequency dependence of quality factors, indicates that scattering is an important factor contributing to the attenuation of body waves in the region. A comparison of Q c and $$ Q_{\beta } $$ in the present study shows that $$ Q_{\beta } < Q_{c} $$ for frequencies below 4Hz and $$ Q_{\beta } > Q_{c} $$ for the frequencies greater than 4Hz. This may be due to the multiple scattering effect of the medium. The outcome of this study is expected to be useful for the estimation of source parameters and near-source simulation of earthquake ground motion, which in turn are required in the seismic hazard assessment of a region. Springer Science+Business Media B.V., 2007 Attenuation nationallicence Coda normalization nationallicence Quality factor nationallicence Seismic waves nationallicence Sharma Babita Institute of Seismological Research, Gandhinagar, India aut Teotia S. Department of Geophysics, Kurukshetra University, 136 119, Kurukshetra, India aut Kumar Dinesh Department of Geophysics, Kurukshetra University, 136 119, Kurukshetra, India aut Journal of Seismology Kluwer Academic Publishers 11/3(2007-07-01), 327-344 1383-4649 11:3<327 2007 11 10950 https://doi.org/10.1007/s10950-007-9057-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10950-007-9057-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Sharma Babita Institute of Seismological Research, Gandhinagar, India aut NATIONALLICENCE 700 1- Teotia S. Department of Geophysics, Kurukshetra University, 136 119, Kurukshetra, India aut NATIONALLICENCE 700 1- Kumar Dinesh Department of Geophysics, Kurukshetra University, 136 119, Kurukshetra, India aut NATIONALLICENCE 773 0- Journal of Seismology Kluwer Academic Publishers 11/3(2007-07-01), 327-344 1383-4649 11:3<327 2007 11 10950 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer