Research Abstract


Disturbance of deep-sea environments induced by the M9.0 Tohoku Earthquake

2012年2月16日 Scientific Reports 2 : 270 doi: 10.1038/srep00270


川口 慎介1,2, 吉田(高島)ゆかり3, 野口 拓郎4, 本多 牧生5, 内田 裕5, 石橋 秀規6, 中川 書子6, 角皆 潤6, 岡村 慶4, 高木 善弘3, 布浦 拓郎3, 宮崎 淳一1,2,3, 平井 美穂3, 林 為人7, 北里 洋3 & 高井 研1,2,3

  1. 海洋研究開発機構 プレカンブリアンエコシステムラボユニット
  2. 海洋研究開発機構 海底資源研究プロジェクト
  3. 海洋研究開発機構 海洋・極限環境生物圏領域
  4. 高知大学 海洋コア総合研究センター
  5. 海洋研究開発機構 地球環境変動領域
  6. 北海道大学 理学研究院
  7. 海洋研究開発機構 高知コア研究所
The impacts of the M9.0 Tohoku Earthquake on deep-sea environment were investigated 36 and 98 days after the event. The light transmission anomaly in the deep-sea water after 36 days became atypically greater (∼35%) and more extensive (thickness ∼1500 m) near the trench axis owing to the turbulent diffusion of fresh seafloor sediment, coordinated with potential seafloor displacement. In addition to the chemical influx associated with sediment diffusion, an influx of 13C-enriched methane from the deep sub-seafloor reservoirs was estimated. This isotopically unusual methane influx was possibly triggered by the earthquake and its aftershocks that subsequently induced changes in the sub-seafloor hydrogeologic structures. The whole prokaryotic biomass and the development of specific phylotypes in the deep-sea microbial communities could rise and fall at 36 and 98 days, respectively, after the event. We may capture the snap shots of post-earthquake disturbance in deep-sea chemistry and microbial community responses.