Relationship between volcanic activity and chemical composition of volcanic gases - A case study on the Sakurajima Volcano.

Temporal variation in the chemical composition (HCl/SO2) of volcanic gas associated with the volcanic activity of Aso Volcano, Japan

“…Among the various chemical compositions, the ratio of HCl/SO 2 or Cl/S is often used as an indicator of volcanic activity. However, the variation of these ratios with volcanic activity differs among volcanoes: increases (e.g., Hirabayashi et al, 1982;Aiuppa et al, 2004) and decreases (e.g., Noguchi and Kamiya, 1963;Taran et al, 2002;Duffel et al, 2003) of these ratios are reported to be associated with increasing volcanic activity. In the case of Aso volcano, high HCl/SO 2 ratios were observed soon after intense eruptive activities, and subsequently decreased after the activities ceased (Iwasaki et al, 1962;Ossaka et al, 1978Ossaka et al, , 1984.…”

Microbial biomineralization in weathered volcanic ash deposit and formation of biogenic minerals by experimental incubation

“…Brought to you by | New York University Bobst Library Technical Services Authenticated Download Date | 7/14/15 4:33 PM ash by interaction with the pore water, but the Cland SO 4 2may be from new ash fall regime and/or from volcanic gases emitted by Sakurajima volcano because the amounts of SO 2 , N 2 , HCl, and HF discharged from the summit crater are estimated to be 1-2000 ton/day (Hirabayashi et al 1982). The saturation indices (SI) calculated by the PHREEQC geochemical code (Table 4) for amorphous Al(OH) 3 , ferrihydrite, amorphous silica, and cristobalite are close to SI = 0, indicating that the pore water is almost saturated with respect to these minerals.…”

Remote determinations on fumarole outlet temperatures in an eruptive volcano

“…In general, a volcanic plume spreads laterally at a height close to or slightly higher than the summit of the volcano from which it was ejected so that its height is significantly higher than sea/ground level. As a result, flying devices such as aircraft [e.g., Fiske and Sigurdsson, 1982;Hirabayashi et al, 1982;Saiki and Ohba, 2010;Shinohara et al, 2003] are needed to obtain samples of volcanic plumes when using HIReTS for eruptive volcanoes. Development of devices for sampling the plume air is needed as well.…”