For estimating fatalities and injured within minutes after an earthquake worldwide, we rely on real-time teleseismic determinations of epicenters. To estimate the teleseismic location errors, we computed the difference between the local epicenters of the dense seismograph networks of Japan, Italy, and Taiwan with those given by the PDE, those distributed in real time by the U.S. Geological Survey (USGS), and the European Mediterranean Seismological Center (EMSC). The average difference is 16 and 8 km between PDE teleseismic epicenters and those by the local networks for Japan/Taiwan and Italy, respectively. For EMSC epicenters, the average difference is 13 km for Italy. The average difference between real-time USGS parameters and those listed in the PDE is 12 km (median 9 km) for 30 earthquakes in Japan. Comparisons of real-time USGS epicenters and the Japan Meterological Agency (JMA) locations yield an average difference of 31 km (median 26 km). Estimates indicate that the epicenter errors in the local catalogs are typically 1 and 3 km for Japan/Italy and Taiwan, respectively. Assuming that the differences in earthquake locations are mostly due to teleseiseismic errors, we conclude that the mean errors in real-time epicenter solutions are in the range of 25 to 35 km. This implies that for earthquakes of M ≈ 6:7 in the vicinity of a medium-sized city (80,000), the fatality estimates using QLARM in real time have to range from near 0 to 10,000 in the developing world and from 0 to 500 in an industrialized country. These results were verified by comparison with observed numbers of fatalities in the cases of the 2003 M 6.7 Bam, Iran, and the 2008 M 6.9 Iwate-Miyagi, Japan, earthquakes.
Three hundred and thirty-five local earthquakes were processed and the attenuation properties of the crust in the Racha region were investigated using the records of seven seismic stations. We have estimated the quality factors of coda waves ([Formula: see text]) and the direct [Formula: see text] waves ([Formula: see text]) by the single back scattering model and the coda normalization methods, respectively. The Wennerberg’s method has been used to estimate relative contribution of intrinsic ([Formula: see text]) and scattering ([Formula: see text]) attenuations in the total attenuation. We have found that [Formula: see text] and [Formula: see text] parameters are frequency-dependent in the frequency range of 1.5–24[Formula: see text]Hz. [Formula: see text] values increase both with respect to lapse time window from 20[Formula: see text]s to 60[Formula: see text]s and frequency. [Formula: see text] and [Formula: see text] parameters are nearly similar for all frequency bands, but are smaller than [Formula: see text]. The obtained results show that the intrinsic attenuation has more significant effect than scattering attenuation in the total attenuation. The increase of [Formula: see text] with lapse time shows that the lithosphere becomes more homogeneous with depth.
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