Fig. 8

Horizontal elastic spectral acceleration motion at TMDA (thick black line), SRDT, and PRAC (grey lines) during six events in Table 2 with 5% damping ratio. The thick dot lines show horizontal spectrum for selected windows contains only the body waves (without surface waves). The estimated median horizontal spectrum computed from Boore et al. (2014) and Zhao et al. (2006) are shown in red and green, respectively. The thick black dash lines show horizontal elastic response spectra of TMDB (borehole)