Fig. 3

Vertical cross sections of \(Q_{\text{P}}^{ - 1}\) and \(Q_{\text{S}}^{ - 1}\) structures and topography along lines A–B, B–C, and C–D. The region shaded by gray shows low resolution, where the resolvability R of the CRTs is smaller than 0.75. The Conrad and Moho discontinuities in the model are drawn by dashed lines. Green, yellow, and sky blue stars indicate the hypocenters of the largest foreshock (M _JMA6.5), the mainshock (M _JMA7.3), and the induced event (M _JMA5.7), respectively. White stars denote the hypocenters of events larger than M _JMA5.0 for 1 month following the foreshock. Black dots indicate the events with 2.0 ≤ M _JMA < 5.0 occurring for 1 month following the foreshock. See the caption of Fig. 1 for explanation of the triangle symbols