Figure 2
Examples of results obtained for an earthquake (M3.9) with a depth of 79 km. (a) Map showing path-average Q p -1 plotted at station locations (colored squares). Colors represent Q p -1 values and color scales are shown in (b). The epicenter of the M3.9 earthquake is shown by a red star. (b) Vertical cross section of the Q p -1 model obtained in this study along latitude of 35.6 °N. Stations and earthquakes located in the gray band in (a) are shown by colored squares and gray circles, respectively. Black lines denote ray paths from the M3.9 earthquake (red star) to four stations (N.CHSH, N.YKIH, TOKYO, and N.FJOH) that are calculated with a 3-D P-wave velocity model (Nakajima et al. 2009). Dashed lines denote the upper surfaces of the Philippine Sea and Pacific slabs (Hirose et al. 2008; Nakajima et al. 2009). (c) Spectral amplitudes for P waves (black line) and noises (dashed line) observed at the four stations. The names of stations are shown above each panel. A red line represents the theoretical spectral amplitude calculated with t0*, site-amplification factors, and the ω2 source model. (d) Spectral amplitudes for P waves (black line) and noises (dashed line) corrected for site-amplification factors. A red line represents the theoretical spectral amplitude calculated with t0* and the ω2 source model. Inverted triangles denote the P-wave corner frequency of the M3.9 earthquake. Values of t0* and path-average Q p -1 are shown above each panel. (e) Site amplification factors estimated for the four stations.