Re–Os isotope geochemistry in the surface layers of ferromanganese crusts from the Takuyo Daigo Seamount, northwestern Pacific Ocean

  • Tokumaru Ayaka
    Department of Earth and Planetary Science, The University of Tokyo Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
  • Nozaki Tatsuo
    Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Submarine Resources Research Project (SRRP), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Department of Systems Innovation, The University of Tokyo
  • Suzuki Katsuhiko
    Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Submarine Resources Research Project (SRRP), Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
  • Goto Kosuke T.
    Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Geological Survey of Japan (GSJ), National Institute of Advanced Industrial Science and Technology (AIST)
  • Chang Qing
    Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Submarine Resources Research Project (SRRP), Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
  • Kimura Jun-ichi
    Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
  • Takaya Yutaro
    Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Frontier Research Center for Energy and Resources (FRCER), School of Engineering, The University of Tokyo
  • Kato Yasuhiro
    Institute for Research on Earth Evolution (IFREE), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Submarine Resources Research Project (SRRP), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Department of Systems Innovation, The University of Tokyo Frontier Research Center for Energy and Resources (FRCER), School of Engineering, The University of Tokyo
  • Usui Akira
    Submarine Resources Research Project (SRRP), Japan Agency for Marine-Earth Science and Technology (JAMSTEC) Department of Geology, Natural Sciences Cluster, Kochi University
  • Urabe Tetsuro
    Department of Earth and Planetary Science, The University of Tokyo

この論文をさがす

説明

Os isotope compositions in ferromanganese crusts (Fe–Mn crusts) have been used for the dating of model ages from present to the Late Cretaceous. This dating method assumes that the Fe–Mn crusts preserve a paleo-seawater Os isotope composition at the timing of Fe–Mn crust deposition. However, available Os isotope data are limited to dredged samples without precise indications of water depths, and the Os isotope variation in relation to water depth remains uncertain. Here, we report on the Os isotope ratio data in the surface layer of Fe–Mn crusts from 956–2987 meters below sea level at the Takuyo Daigo Seamount in the northwestern Pacific Ocean collected by a remotely operated vehicle (ROV). Since the 187Re/188Os ratios of the surface layer samples exhibited low values ranging from 0.020 to 0.0078, the age correction of the 187Os/188Os ratios by subtracting radiogenic 187Os from total 187Os was not necessary for the Takuyo Daigo Fe–Mn crusts. Regardless of water depth, the surface layer samples possessed a narrow range of 187Os/188Os ratio (1.003–1.017). As their Os isotope ratios were very similar to or slightly lower than the present-day seawater value (~1.06), the Fe–Mn crusts are inferred to preserve the modern seawater Os isotope composition at the investigated water depths. Therefore, Os isotope stratigraphy using Fe–Mn crusts is a powerful dating tool in paleoceanography.

収録刊行物

被引用文献 (17)*注記

もっと見る

参考文献 (32)*注記

もっと見る

関連プロジェクト

もっと見る

詳細情報 詳細情報について

問題の指摘

ページトップへ