Fig. 4From: Influence of hydrothermal recharge on the evolution of eruption styles and hazards during the 2018–2019 activity at Kuchinoerabujima Volcano, JapanTemporal variation of X-ray peak intensities of alteration minerals versus rock-forming minerals. The ratios refer to the total peak intensity of maximum peaks of silica minerals of tridymite, cristobalite, and quartz (silica/Pl); sulfate minerals of gypsum, anhydrite, and alunite (sulfate/Pl); and sulfide mineral of pyrite (sulfide/Pl), divided by the maximum peak intensity of plagioclase (Pl), respectivelyBack to article page