4. Volcanic Gases and Sublimates of Akita-komagatake(VI. Materials Erupted during the 1970-71 Activity of Akita-Komagatake)

Abstract

The content of the volcanic gases were measured for the period of activity of Akita Komagatake from 1970 to 1971. The results are as follows : CO₂ 300～930, SO₂ 0.4～2.5, HCl 8.9～66, HF 3.6～9.4, NH₃ 4.0～26ml/1000l. Presence of Halite (NaCl), Fluorite (CaF₂), and Anhydrite (CaSO₄) were identified in the volcanic sublimates. Relation among the volcanie gases, sublimates, and volatile matters in ejecta was investigated. The origin of volatile matter contained in the magma thrown out during the eruption was also discussed.