Fig. 3

Ocean-bottom pressure waveforms and scalograms at S1N04 and S4N22 in S-net and KMC10 and MRE18 in DONET, which are shown in Fig. 1a. The results of the semblance analysis using waveforms at each station and their neighboring stations (listed in parentheses) are also shown. Cyan lines in the plots of direction-of-arrival indicate the direction of the short great circle from each station to the Hunga Tonga–Hunga Ha’apai volcano. Gray shading in the plots of velocity denotes the propagation velocity range expected for the water depth of the stations in each array. Gray dashed lines indicate the theoretical arrival times of direct tsunamis. Green and pink bars indicate the theoretical travel times assuming propagation along the short great circle path from the Hunga Tonga‒Hunga Ha’apai volcano at the velocities of 300 and 220 m/s, respectively