Theory for Deducing Volcanic Activity From Size Distributions in Plinian Pyroclastic Fall Deposits

Yu Iriyama, Atsushi Toramaru, Tetsuo Yamamoto

研究成果: ジャーナルへの寄稿記事

1 引用 (Scopus)

抄録

Stratigraphic variation in the grain size distribution (GSD) of plinian pyroclastic fall deposits reflects volcanic activity. To extract information on volcanic activity from the analyses of deposits, we propose a one-dimensional theory that provides a formula connecting the sediment GSD to the source GSD. As the simplest case, we develop a constant-source model (CS model), in which the source GSD and the source height are constant during the duration of release of particles. We assume power laws of particle radii for the terminal fall velocity and the source GSD. The CS model can describe an overall (i.e., entire vertically variable) feature of the GSD structure of the sediment. It is shown that the GSD structure is characterized by three parameters, that is, the duration of supply of particles to the source scaled by the fall time of the largest particle, ts/tM, and the power indices of the terminal fall velocity p and of the source GSD q. We apply the CS model to samples of the Worzel D ash layer and compare the sediment GSD structure calculated by using the CS model to the observed structure. The results show that the CS model reproduces the overall structure of the observed GSD. We estimate the duration of the eruption and the q value of the source GSD. Furthermore, a careful comparison of the observed and calculated GSDs reveals new interpretation of the original sediment GSD structure of the Worzel D ash layer.

元の言語英語
ページ(範囲)2199-2213
ページ数15
ジャーナルJournal of Geophysical Research: Solid Earth
123
発行部数3
DOI
出版物ステータス出版済み - 3 2018

Fingerprint

volcanology
Deposits
grain size
deposits
Ashes
Sediments
sediments
ashes
sediment
ash
volcanic eruptions
power law
volcanic eruption
radii
particle
estimates

All Science Journal Classification (ASJC) codes

  • Geophysics
  • Geochemistry and Petrology
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science

これを引用

Theory for Deducing Volcanic Activity From Size Distributions in Plinian Pyroclastic Fall Deposits. / Iriyama, Yu; Toramaru, Atsushi; Yamamoto, Tetsuo.

:: Journal of Geophysical Research: Solid Earth, 巻 123, 番号 3, 03.2018, p. 2199-2213.

研究成果: ジャーナルへの寄稿記事

@article{dc983c2194a64fcba8a31051e1c31f0f,
title = "Theory for Deducing Volcanic Activity From Size Distributions in Plinian Pyroclastic Fall Deposits",
abstract = "Stratigraphic variation in the grain size distribution (GSD) of plinian pyroclastic fall deposits reflects volcanic activity. To extract information on volcanic activity from the analyses of deposits, we propose a one-dimensional theory that provides a formula connecting the sediment GSD to the source GSD. As the simplest case, we develop a constant-source model (CS model), in which the source GSD and the source height are constant during the duration of release of particles. We assume power laws of particle radii for the terminal fall velocity and the source GSD. The CS model can describe an overall (i.e., entire vertically variable) feature of the GSD structure of the sediment. It is shown that the GSD structure is characterized by three parameters, that is, the duration of supply of particles to the source scaled by the fall time of the largest particle, ts/tM, and the power indices of the terminal fall velocity p and of the source GSD q. We apply the CS model to samples of the Worzel D ash layer and compare the sediment GSD structure calculated by using the CS model to the observed structure. The results show that the CS model reproduces the overall structure of the observed GSD. We estimate the duration of the eruption and the q value of the source GSD. Furthermore, a careful comparison of the observed and calculated GSDs reveals new interpretation of the original sediment GSD structure of the Worzel D ash layer.",
author = "Yu Iriyama and Atsushi Toramaru and Tetsuo Yamamoto",
year = "2018",
month = "3",
doi = "10.1002/2017JB014782",
language = "English",
volume = "123",
pages = "2199--2213",
journal = "Journal of Geophysical Research",
issn = "0148-0227",
publisher = "American Geophysical Union",
number = "3",

}

TY - JOUR

T1 - Theory for Deducing Volcanic Activity From Size Distributions in Plinian Pyroclastic Fall Deposits

AU - Iriyama, Yu

AU - Toramaru, Atsushi

AU - Yamamoto, Tetsuo

PY - 2018/3

Y1 - 2018/3

N2 - Stratigraphic variation in the grain size distribution (GSD) of plinian pyroclastic fall deposits reflects volcanic activity. To extract information on volcanic activity from the analyses of deposits, we propose a one-dimensional theory that provides a formula connecting the sediment GSD to the source GSD. As the simplest case, we develop a constant-source model (CS model), in which the source GSD and the source height are constant during the duration of release of particles. We assume power laws of particle radii for the terminal fall velocity and the source GSD. The CS model can describe an overall (i.e., entire vertically variable) feature of the GSD structure of the sediment. It is shown that the GSD structure is characterized by three parameters, that is, the duration of supply of particles to the source scaled by the fall time of the largest particle, ts/tM, and the power indices of the terminal fall velocity p and of the source GSD q. We apply the CS model to samples of the Worzel D ash layer and compare the sediment GSD structure calculated by using the CS model to the observed structure. The results show that the CS model reproduces the overall structure of the observed GSD. We estimate the duration of the eruption and the q value of the source GSD. Furthermore, a careful comparison of the observed and calculated GSDs reveals new interpretation of the original sediment GSD structure of the Worzel D ash layer.

AB - Stratigraphic variation in the grain size distribution (GSD) of plinian pyroclastic fall deposits reflects volcanic activity. To extract information on volcanic activity from the analyses of deposits, we propose a one-dimensional theory that provides a formula connecting the sediment GSD to the source GSD. As the simplest case, we develop a constant-source model (CS model), in which the source GSD and the source height are constant during the duration of release of particles. We assume power laws of particle radii for the terminal fall velocity and the source GSD. The CS model can describe an overall (i.e., entire vertically variable) feature of the GSD structure of the sediment. It is shown that the GSD structure is characterized by three parameters, that is, the duration of supply of particles to the source scaled by the fall time of the largest particle, ts/tM, and the power indices of the terminal fall velocity p and of the source GSD q. We apply the CS model to samples of the Worzel D ash layer and compare the sediment GSD structure calculated by using the CS model to the observed structure. The results show that the CS model reproduces the overall structure of the observed GSD. We estimate the duration of the eruption and the q value of the source GSD. Furthermore, a careful comparison of the observed and calculated GSDs reveals new interpretation of the original sediment GSD structure of the Worzel D ash layer.

UR - http://www.scopus.com/inward/record.url?scp=85044294371&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85044294371&partnerID=8YFLogxK

U2 - 10.1002/2017JB014782

DO - 10.1002/2017JB014782

M3 - Article

AN - SCOPUS:85044294371

VL - 123

SP - 2199

EP - 2213

JO - Journal of Geophysical Research

JF - Journal of Geophysical Research

SN - 0148-0227

IS - 3

ER -