Fig. 7

Epicenter map of tectonic tremors estimated with the method of Imanishi et al. (2011) during an S-SSE from 3 February 2019 to 6 February 2019 (Japan Meteorological Agency 2019). The rectangle on each map shows a fault model of the S-SSE; the red line segment on the rectangle indicates the upper edge of the fault. The black circles denote tectonic tremor epicenters in the period shown at each panel, and the red circles tectonic tremor epicenters during the strain steps shown in Fig. 5c,d and Table 2