8 0 0 0 OA 特集「次世代研究者のための火山学講座」
2 0 0 0 OA 火山噴火の素過程に関する実験的·理論的研究
- 著者
- 吉村 俊平
- 出版者
- 特定非営利活動法人日本火山学会
- 雑誌
- 火山 (ISSN:04534360)
- 巻号頁・発行日
- vol.61, no.4, pp.605-613, 2016-12-31 (Released:2017-01-13)
- 参考文献数
- 37
1 0 0 0 OA 火山ガラス中のH2O・CO2 の赤外分光分析
- 著者
- 吉村 俊平
- 出版者
- 特定非営利活動法人 日本火山学会
- 雑誌
- 火山 (ISSN:04534360)
- 巻号頁・発行日
- vol.66, no.4, pp.375-384, 2021-12-31 (Released:2022-02-22)
- 参考文献数
- 24
1 0 0 0 OA 石基ガラスの塩素濃度不均質から読み解く珪長質マグマの脱ガス現象
- 著者
- 吉村 俊平
- 出版者
- 一般社団法人 日本鉱物科学会
- 雑誌
- 岩石鉱物科学 (ISSN:1345630X)
- 巻号頁・発行日
- vol.49, no.2, pp.51-57, 2020 (Released:2020-11-03)
- 参考文献数
- 35
Despite its water-rich nature, silicic magma often erupts calmly to discharge bubble-poor lava without accompanying violent explosion. To allow a water-rich magma to avoid explosion, gas phase that forms as a result of decompressive exsolution needs to escape efficiently to the outside of the magma. However, mechanism of this gas escape has long been unclear, mainly because direct evidence of gas pathways is rarely preserved in natural lava samples. In this paper I show that chlorine-content mapping analysis successfully visualizes the gas pathways hidden in groundmass glass. This chlorine mapping analysis was developed based on an idea that chlorine diffusivity in rhyolitic melt is so low that chlorine heterogeneity formed through degassing processes may survive for a long time without being homogenized. Timescales of degassing processes are estimated by applying a diffusion model to the observed heterogeneity. Results of my recent chlorine diffusion experiments are also presented, as the chlorine diffusivity is the key for interpreting the observed heterogeneity.