海域に流入した北海道駒ケ岳火山1640年岩屑なだれ堆積物の分布と体積推定

書誌事項

タイトル別名
  • Subaqueous distribution and volume estimation of the debris-avalanche deposit from the 1640 eruption of Hokkaido-Komagatake volcano, southwest Hokkaido, Japan
  • カイイキ ニ リュウニュウ シタ ホッカイドウ コマガタケ カザン 1640ネン ガンセツ ナダレ タイセキブツ ノ ブンプ ト タイセキ スイテイ

この論文をさがす

抄録

Sidescan sonar and sub-bottom reflection surveys off the town of Shikabe, along the Pacific coast of southwest Hokkaido, show the extent and volume of a submarine debris-avalanche deposit caused by the A. D. 1640 eruption of Hokkaido-Komagatake volcano. The avalanche extends succesively from the subaerial part of the Shikabe lobe, and traveled as far as 20 km seaward from the volcano. Subaqueous deposit reached the 80m-deep seafloor and bifurcated northward and eastward. It covered 126 km2 of the seafloor with 15km width. Hummocks of the subaqueous deposit decrease in height and width with distance, like progressively shattered hummocks of subaerial debris-avalanche deposits. The marginal region of the deposit lacks hummocks and shows a prominent flow front slope, implying the presence of a yield strength of the debris-avalanche deposit. The ratio of height to the distance of travel (H/L) is 0.06, suggesting more mobile origin than many subaerial debris-avalanche deposits. The subaqueous volume of the avalanche, estimated by extrapolating pre-eruptive topography from the surrounding area, ranges from 0.92 to 1.20 km3, which is larger than the previous estimates. This explains the discrepancy of tsunami simulation results which have been underestimating run-up heights.

収録刊行物

  • 地質学雑誌

    地質学雑誌 109 (10), 595-606, 2003

    一般社団法人 日本地質学会

被引用文献 (13)*注記

もっと見る

参考文献 (32)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ