JaLCDOI 10.18926/ESR/13943
Title Alternative Water-soluble materials on volcanic ash from the 1990-94 eruption of the Unzenn volcano
FullText URL ESR_2_55.pdf
Author Akagi, Seishi| Yamamoto, Masahiro|
Abstract Water-soluble materials on volcanic ash from the Unzen volcano collected from February, 1991 to July, 1994 were chemically analyzed. They were similar in chemical characteristics to those obtained from other volcanoes. Chemical compositions varied even for materials from the same pyroclastic flow. C1 contens increased with increasing residence time of volcanic ash in air, but SO4 contents were almost fixed. It therefore seems that the reaction of volcanic ash with HC1 proceeds even at low temperatures, whereas the reaction with SO2 takes place only at high temperatutes.
Keywords volcanic ash volcanic gas Unzen volcano C1/SO4 ratio water-soluble material
Publication Title Okayama University Earth Science Report
Published Date 1995-09-20
Volume volume2
Issue issue1
Start Page 55
End Page 62
ISSN 1340-7414
language 日本語
Copyright Holders 岡山大学地球科学研究報告編集委員会
File Version publisher
NAID 120002310484
JaLCDOI 10.18926/ESR/13897
Title Alternative Water-soluble materials formed by the reaction between a volcanic rock and HCI and/or SO2 gases
FullText URL ESR_7_21.pdf
Author Akagi, Seishi| Yamamoto, Masahiro|
Abstract Experiments on the reaction of a volcanic rock, dacite with HCI and /or SO2 gases have been carried out at room temperature to 800℃ for understanding of the condition of the formation of water-soluble materials on volcanic ash. HCI reacted with the dacite mainly at low temperatures (≤200℃), whereas SO2 did at high temperatures (≥400℃). It was also found that CI/SO4 ratios of water-soluble materials were very high at low temperatures, but decreased rapidly with increasing temperature. In the experiments using a mixture of HCI and SO2, the cation composition at 600℃ and 800℃ was revealed to be significantly different from that at lower temperatures, suggesting the change in the reaction process with temperature.
Keywords Volcanic gas Volcanic ash Water-soluble material CI/SO4 ratio
Publication Title Okayama University Earth Science Report
Published Date 2000-09-20
Volume volume7
Issue issue1
Start Page 21
End Page 26
ISSN 1340-7414
language 日本語
Copyright Holders 岡山大学地球科学研究報告編集委員会
File Version publisher
NAID 120002310554