Fig. 1

Map of Mount Ontake with approximate positions of casualties based on journal reports (Asahi Shimbun Newspaper, October 27, 2014, p. 35; Yamanashi Nichinichi Shimbun Newspaper, September 26, 2015, p. 19). The numbers on the map represent the number of casualties at each site. The eruption left 58 people dead, and five people are still missing. The locations of the vents were taken from the Web site for the Geospatial Information Authority of Japan (2014). The position of the vent labeled “Center Vent” was used as the ejection position of ballistic blocks in our 3D multiparticle numerical simulations