Major and trace element compositions and resource potential of ferromanganese crust at Takuyo Daigo Seamount, northwestern Pacific Ocean

Tatsuo Nozaki, Ayaka Tokumaru, Yutaro Takaya, Yasuhiro Kato, Katsuhiko Suzuki, Tetsuro Urabe

    Research output: Contribution to journalArticle

    8 Citations (Scopus)

    Abstract

    We report major element and trace element compositions of ferromanganese crusts (Fe-Mn crusts) on Takuyo Daigo Seamount, northwestern Pacific Ocean. Highly enriched elements in these crusts, such as Co (6500 ppm), Ni (4000 ppm), Mo (520 ppm), Te (39 ppm), W (92 ppm), Pt (0.19 ppm), and rare earth elements (REEs; ΣREE = 1700 ppm), exhibit strong positive correlations with either Fe or Mn concentrations. Chemical analyses of the crusts show that the Fe/Mn ratio decreases toward shallower water and older deposits. Thus, deeper or younger crust is more promising as a REE (other than Ce) resource, and shallower or older crust has a greater potential as Co, Ni, Ce, and Pt resources. REE profiles of Fe-Mn crusts with less than 0.5 wt% P, normalized to post-Archean average Australian shale, are flat with positive Ce anomalies whereas samples with more than 0.5 wt% P are enriched in heavy REE, and four samples from deep in the crusts with more than 2.2 wt% P do not exhibit positive Ce anomalies. These differences in REE patterns can be explained by mixing of Fe-Mn oxide and Ca-phosphate minerals (apatite). Assuming that Fe-Mn crusts with 5 cm thickness and 1.29 g/cm3 dry density are homogeneously distributed at water depths from 1000 to 3000 m along the 500 km perimeter of Takuyo Daigo Seamount, the possible reserve represented by Fe-Mn crusts is roughly 65 Mt of ore. Based on the average concentrations obtained here, resource amounts at Takuyo Daigo Seamount are 420 ×103 t Co, 110 ×103 tREO, 2500 t Dy, and 440 t Tb, comparable to the known reserves of major mineral producing nations. Thus, Fe-Mn crusts in the northwestern Pacific Ocean have a notable potential as a source of Co.

    Original languageEnglish
    Pages (from-to)527-537
    Number of pages11
    JournalGeochemical Journal
    Volume50
    Issue number6
    DOIs
    Publication statusPublished - 2016

    Fingerprint

    seamounts
    Pacific Ocean
    Trace Elements
    seamount
    trace elements
    crusts
    resources
    trace element
    crust
    rare earth element
    ocean
    resource
    Chemical analysis
    Phosphate minerals
    Apatites
    Water
    minerals
    Shale
    Rare earth elements
    Oxides

    Keywords

    • Fe-mn crust
    • Northwestern pacific ocean
    • Resource potential evaluation
    • Takuyo daigo seamount

    ASJC Scopus subject areas

    • Geophysics
    • Geochemistry and Petrology

    Cite this

    Major and trace element compositions and resource potential of ferromanganese crust at Takuyo Daigo Seamount, northwestern Pacific Ocean. / Nozaki, Tatsuo; Tokumaru, Ayaka; Takaya, Yutaro; Kato, Yasuhiro; Suzuki, Katsuhiko; Urabe, Tetsuro.

    In: Geochemical Journal, Vol. 50, No. 6, 2016, p. 527-537.

    Research output: Contribution to journalArticle

    Nozaki, Tatsuo ; Tokumaru, Ayaka ; Takaya, Yutaro ; Kato, Yasuhiro ; Suzuki, Katsuhiko ; Urabe, Tetsuro. / Major and trace element compositions and resource potential of ferromanganese crust at Takuyo Daigo Seamount, northwestern Pacific Ocean. In: Geochemical Journal. 2016 ; Vol. 50, No. 6. pp. 527-537.
    @article{c052c1e0828f4b22a8bf9962bb45019b,
    title = "Major and trace element compositions and resource potential of ferromanganese crust at Takuyo Daigo Seamount, northwestern Pacific Ocean",
    abstract = "We report major element and trace element compositions of ferromanganese crusts (Fe-Mn crusts) on Takuyo Daigo Seamount, northwestern Pacific Ocean. Highly enriched elements in these crusts, such as Co (6500 ppm), Ni (4000 ppm), Mo (520 ppm), Te (39 ppm), W (92 ppm), Pt (0.19 ppm), and rare earth elements (REEs; ΣREE = 1700 ppm), exhibit strong positive correlations with either Fe or Mn concentrations. Chemical analyses of the crusts show that the Fe/Mn ratio decreases toward shallower water and older deposits. Thus, deeper or younger crust is more promising as a REE (other than Ce) resource, and shallower or older crust has a greater potential as Co, Ni, Ce, and Pt resources. REE profiles of Fe-Mn crusts with less than 0.5 wt{\%} P, normalized to post-Archean average Australian shale, are flat with positive Ce anomalies whereas samples with more than 0.5 wt{\%} P are enriched in heavy REE, and four samples from deep in the crusts with more than 2.2 wt{\%} P do not exhibit positive Ce anomalies. These differences in REE patterns can be explained by mixing of Fe-Mn oxide and Ca-phosphate minerals (apatite). Assuming that Fe-Mn crusts with 5 cm thickness and 1.29 g/cm3 dry density are homogeneously distributed at water depths from 1000 to 3000 m along the 500 km perimeter of Takuyo Daigo Seamount, the possible reserve represented by Fe-Mn crusts is roughly 65 Mt of ore. Based on the average concentrations obtained here, resource amounts at Takuyo Daigo Seamount are 420 ×103 t Co, 110 ×103 tREO, 2500 t Dy, and 440 t Tb, comparable to the known reserves of major mineral producing nations. Thus, Fe-Mn crusts in the northwestern Pacific Ocean have a notable potential as a source of Co.",
    keywords = "Fe-mn crust, Northwestern pacific ocean, Resource potential evaluation, Takuyo daigo seamount",
    author = "Tatsuo Nozaki and Ayaka Tokumaru and Yutaro Takaya and Yasuhiro Kato and Katsuhiko Suzuki and Tetsuro Urabe",
    year = "2016",
    doi = "10.2343/geochemj.2.0430",
    language = "English",
    volume = "50",
    pages = "527--537",
    journal = "Geochemical Journal",
    issn = "0016-7002",
    publisher = "The Physiological Society of Japan",
    number = "6",

    }

    TY - JOUR

    T1 - Major and trace element compositions and resource potential of ferromanganese crust at Takuyo Daigo Seamount, northwestern Pacific Ocean

    AU - Nozaki, Tatsuo

    AU - Tokumaru, Ayaka

    AU - Takaya, Yutaro

    AU - Kato, Yasuhiro

    AU - Suzuki, Katsuhiko

    AU - Urabe, Tetsuro

    PY - 2016

    Y1 - 2016

    N2 - We report major element and trace element compositions of ferromanganese crusts (Fe-Mn crusts) on Takuyo Daigo Seamount, northwestern Pacific Ocean. Highly enriched elements in these crusts, such as Co (6500 ppm), Ni (4000 ppm), Mo (520 ppm), Te (39 ppm), W (92 ppm), Pt (0.19 ppm), and rare earth elements (REEs; ΣREE = 1700 ppm), exhibit strong positive correlations with either Fe or Mn concentrations. Chemical analyses of the crusts show that the Fe/Mn ratio decreases toward shallower water and older deposits. Thus, deeper or younger crust is more promising as a REE (other than Ce) resource, and shallower or older crust has a greater potential as Co, Ni, Ce, and Pt resources. REE profiles of Fe-Mn crusts with less than 0.5 wt% P, normalized to post-Archean average Australian shale, are flat with positive Ce anomalies whereas samples with more than 0.5 wt% P are enriched in heavy REE, and four samples from deep in the crusts with more than 2.2 wt% P do not exhibit positive Ce anomalies. These differences in REE patterns can be explained by mixing of Fe-Mn oxide and Ca-phosphate minerals (apatite). Assuming that Fe-Mn crusts with 5 cm thickness and 1.29 g/cm3 dry density are homogeneously distributed at water depths from 1000 to 3000 m along the 500 km perimeter of Takuyo Daigo Seamount, the possible reserve represented by Fe-Mn crusts is roughly 65 Mt of ore. Based on the average concentrations obtained here, resource amounts at Takuyo Daigo Seamount are 420 ×103 t Co, 110 ×103 tREO, 2500 t Dy, and 440 t Tb, comparable to the known reserves of major mineral producing nations. Thus, Fe-Mn crusts in the northwestern Pacific Ocean have a notable potential as a source of Co.

    AB - We report major element and trace element compositions of ferromanganese crusts (Fe-Mn crusts) on Takuyo Daigo Seamount, northwestern Pacific Ocean. Highly enriched elements in these crusts, such as Co (6500 ppm), Ni (4000 ppm), Mo (520 ppm), Te (39 ppm), W (92 ppm), Pt (0.19 ppm), and rare earth elements (REEs; ΣREE = 1700 ppm), exhibit strong positive correlations with either Fe or Mn concentrations. Chemical analyses of the crusts show that the Fe/Mn ratio decreases toward shallower water and older deposits. Thus, deeper or younger crust is more promising as a REE (other than Ce) resource, and shallower or older crust has a greater potential as Co, Ni, Ce, and Pt resources. REE profiles of Fe-Mn crusts with less than 0.5 wt% P, normalized to post-Archean average Australian shale, are flat with positive Ce anomalies whereas samples with more than 0.5 wt% P are enriched in heavy REE, and four samples from deep in the crusts with more than 2.2 wt% P do not exhibit positive Ce anomalies. These differences in REE patterns can be explained by mixing of Fe-Mn oxide and Ca-phosphate minerals (apatite). Assuming that Fe-Mn crusts with 5 cm thickness and 1.29 g/cm3 dry density are homogeneously distributed at water depths from 1000 to 3000 m along the 500 km perimeter of Takuyo Daigo Seamount, the possible reserve represented by Fe-Mn crusts is roughly 65 Mt of ore. Based on the average concentrations obtained here, resource amounts at Takuyo Daigo Seamount are 420 ×103 t Co, 110 ×103 tREO, 2500 t Dy, and 440 t Tb, comparable to the known reserves of major mineral producing nations. Thus, Fe-Mn crusts in the northwestern Pacific Ocean have a notable potential as a source of Co.

    KW - Fe-mn crust

    KW - Northwestern pacific ocean

    KW - Resource potential evaluation

    KW - Takuyo daigo seamount

    UR - http://www.scopus.com/inward/record.url?scp=85007382627&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=85007382627&partnerID=8YFLogxK

    U2 - 10.2343/geochemj.2.0430

    DO - 10.2343/geochemj.2.0430

    M3 - Article

    AN - SCOPUS:85007382627

    VL - 50

    SP - 527

    EP - 537

    JO - Geochemical Journal

    JF - Geochemical Journal

    SN - 0016-7002

    IS - 6

    ER -