Fig. 3

a Component proportions for ash of Cotopaxi-2015 and Tungurahua-2016 eruptions at 6 km distance from the vent. b Solid lines depict the cumulative and dashed lines the weight percent grain size distributions (GSD) of Cotopaxi and Tungurahua eruptions. F1 and F2 are coarse (1 – 0.063 mm) and fine (< 0.063 mm) ash thresholds, respectively. Md is the median and the sorting at D16 and D84. The graphs are based on data from Gaunt et al. (2016) and Gheri (2019)