Fig. 11From: Temporal variations in volumetric magma eruption rates of Quaternary volcanoes in JapanCumulative magma volume erupted from Towada Volcano. A red solid line represents an eruption event. A lilac solid line shows a tendency of the eruption rate. A pink square shows the ranges of volume and age for a volcanic edifice which is undivided into separate eruption events. L to Q is the name of eruption episode (Hayakawa 1985). The caldera-forming Episodes L and N produced the Hachinohe and Ofudo Ignimbrites, respectively. This step diagram was made from Hayakawa (1985), Nakagawa et al. (1986), Yamamoto (2015) and Kudo (unpublished data). Hayakawa (1985) defined the syn-caldera stage as the period from episode Q to L. This paper regards the Episode Q as the last eruptive event in the pre-caldera stage from its geochemical featureBack to article page