| Item type |
学術雑誌論文 / Journal Article(1) |
| 公開日 |
2018-05-16 |
| タイトル |
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タイトル |
Reconstruction of a phreatic eruption on 27 September 2014 at Ontake volcano, central Japan, based on proximal pyroclastic density current and fallout deposits |
| 言語 |
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言語 |
eng |
| DOI |
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関連タイプ |
isIdenticalTo |
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関連識別子 |
https://doi.org/10.1186/s40623-016-0449-6 |
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関連名称 |
10.1186/s40623-016-0449-6 |
| キーワード |
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主題 |
Phreatic eruption, Pyroclastic density current, Ontake volcano, Aggregate, Grain-size distribution, Particle concentration, Flow speed |
| 資源タイプ |
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資源 |
http://purl.org/coar/resource_type/c_6501 |
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タイプ |
journal article |
| 著者 |
Maeno, Fukashi
Nakada, Setsuya
Oikawa, Teruki
Yoshimoto, Mitsuhiro
Komori, Jiro
Ishizuka, Yoshihiro
Takeshita, Yoshihiro
Shimano, Taketo
Kaneko, Takayuki
Nagai, Masashi
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| 信州大学研究者総覧へのリンク |
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氏名 |
Takeshita, Yoshihiro |
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URL |
http://soar-rd.shinshu-u.ac.jp/profile/ja.jVAajVkh.html |
| 出版者 |
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出版者 |
SpringerOpen |
| 引用 |
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内容記述 |
Earth, Planets and Space. 68: 82(2016) |
| 書誌情報 |
Earth, Planets and Space
巻 68,
p. 82,
発行日 2016-05-17
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| 抄録 |
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内容記述 |
The phreatic eruption at Ontake volcano on 27 September 2014, which caused the worst volcanic disaster in the past half-century in Japan, was reconstructed based on observations of the proximal pyroclastic density current (PDC) and fallout deposits. Witness observations were also used to clarify the eruption process. The deposits are divided into three major depositional units (Units A, B, and C) which are characterized by massive, extremely poorly sorted, and multimodal grain-size distribution with 30–50 wt% of fine ash (silt–clay component). The depositional condition was initially dry but eventually changed to wet. Unit A originated from gravity-driven turbulent PDCs in the relatively dry, vent-opening phase. Unit B was then produced mainly by fallout from a vigorous moist plume during vent development. Unit C was derived from wet ash fall in the declining stage. Ballistic ejecta continuously occurred during vent opening and development. As observed in the finest population of the grain-size distribution, aggregate particles were formed throughout the eruption, and the effect of water in the plume on the aggregation increased with time and distance. Based on the deposit thickness, duration, and grain-size data, and by applying a scaling analysis using a depth-averaged model of turbulent gravity currents, the particle concentration and initial flow speed of the PDC at the summit area were estimated as 2 × 10−4–2 × 10−3 and 24–28 m/s, respectively. The tephra thinning trend in the proximal area shows a steeper slope than in similar-sized magmatic eruptions, indicating a large tephra volume deposited over a short distance owing to the wet dispersal conditions. The Ontake eruption provided an opportunity to examine the deposits from a phreatic eruption with a complex eruption sequence that reflects the effect of external water on the eruption dynamics. |
| 資源タイプ（コンテンツの種類） |
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| ISSN |
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収録物識別子タイプ |
EISSN |
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収録物識別子 |
1880-5981 |
| 権利 |
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権利情報 |
© 2016 Maeno et al. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. |
| 出版タイプ |
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出版タイプ |
VoR |
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出版タイプResource |
http://purl.org/coar/version/c_970fb48d4fbd8a85 |
| WoS |
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URL |
http://gateway.isiknowledge.com/gateway/Gateway.cgi?&GWVersion=2&SrcAuth=ShinshuUniv&SrcApp=ShinshuUniv&DestLinkType=FullRecord&DestApp=WOS&KeyUT=000375996500002 |
s40623-016-0449-6.pdf (4.2 MB)
