Osmium model age distribution of the Pacific mantle

• Project/Area Number: 25870162
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Geochemistry/Cosmochemistry; Petrology/Mineralogy/Economic geology
• Research Institution: The University of Tokyo
• Principal Investigator: ISHIKAWA Akira 東京大学, 総合文化研究科, 助教 (20524507)
• Research Collaborator: SUZUKI Katsuhiko 国立研究開発法人海洋研究開発機構, 海底資源開発研究センター, センター長代理 (70251329) ; SENDA Ryoko 独立行政法人海洋研究開発機構, 地球内部物質循環研究分野, 技術研究副主任 (50377991) ; TANI Kenichiro 独立行政法人国立科学博物館, 地学研究部, 研究員 (70359206) ; ISHII Teruaki 公益財団法人深田地質研究所, 研究員 (80111582)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000); Fiscal Year 2014: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2013: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
• Keywords: マントル / オスミウム同位体 / 強親鉄性元素 / 地球化学的不均質 / かんらん岩 / 太平洋 / マントル物質

Outline of Final Research Achievements

In order to understand the chemical structure in the Earth's mantle, reflecting the pattern of mantle convection or mixing efficiency, extents of variations in Os isotope ratios and highly siderophile element concentrations for peridotite-serpentinite recovered from the Pacific area were examined. The results demonstrate that samples from the studied area display almost identical Os-isotope variations to the global population mainly comprised of data from other ocean. This suggests that small-scale heterogeneities created by Proterozoic melt extraction are homogeneously distributed over large scales within the modern convecting mantle.

Research Products

• [Journal Article] In situ oxygen-isotope, major-, and trace-element constraints on the metasomatic modification and crustal origin of a diamondiferous eclogite from Roberts Victor, Kaapvaal Craton (2016)
  • Author(s): Riches, A.J.V., Ickert, R.B., Pearson, D.G., Stern, R.A., Jackson, S.E., Ishikawa, A., Kjarsgaard, B.A., Gurney, J.J.
  • Journal Title: Geochimica et Cosmochimica Acta Volume: 174 Pages: 345-359
  • DOI: 10.1016/j.gca.2015.11.028
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Ultrapotassic Magma from the Deep Mantle, Leucite Hills Lamproite, Wyoming USA (2015)
  • Author(s): Ishikawa, A., Kawai, K.
  • Journal Title: Journal of Geography (Chigaku Zasshi) Volume: 124 Issue: 3 Pages: 515-523
  • DOI: 10.5026/jgeography.124.515
  • NAID: 130005087144
  • ISSN: 0022-135X, 1884-0884
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Geology of the Eoarchean, >3.95 Ga, Nulliak supracrustal rocks in the Saglek Block, northern Labrador, Canada: The oldest geological evidence for plate tectonics (2015)
  • Author(s): Komiya, T., Yamamoto, S., Aoki, S., Sawaki, Y., Ishikawa, A., Tashiro, T., Koshida, K., Shimojo, M., Aoki, K., Collerson, K.
  • Journal Title: Tectonophysics Volume: 662 Pages: 40-66
  • DOI: 10.1016/j.tecto.2015.05.003
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Isotopic evidence for a link between the Lyra Basin and Ontong Java Plateau. The Origin Evolution, and Environmental Impact of Oceanic Large igneous Provinces (2015)
  • Author(s): M. L. G. Tejada, K. Shimizu, K. Suzuki, T. Hanyu, T. Sano, M. Nakanishi, S. Nakai, A. Ishikawa, Q. Chang, T. Miyazaki, Y. Hirahara, T. Takahashi, and R. Senda
  • Journal Title: Geological Society of America Special Paper / Geological Society of America Volume: 511 Pages: 251-269
  • DOI: 10.1130/2015.2511(14)
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Characterization of hydration in the mantle lithosphere: Peridotite xenoliths from the Ontong Java Plateau as an example (2015)
  • Author(s): Demouchy, S., Ishikawa, A., Tommasi, A., Alard, O., Keshav, S.
  • Journal Title: Lithos Volume: 212-215 Pages: 189-201
  • DOI: 10.1016/j.lithos.2014.11.005
  • Peer Reviewed
• [Journal Article] Re-Os isotope and platinum group elements of a FOcal ZOne mantle source, Louisville Seamounts Chain, Pacific ocean (2015)
  • Author(s): Tejada, M.L.G., Hanyu, T., Ishikawa, A., Senda, R., Suzuki, K., Fitton, G., Williams, R.
  • Journal Title: Geochemistry Geophysics Geosystems Volume: 16 Issue: 2 Pages: 486-504
  • DOI: 10.1002/2014gc005629
  • Peer Reviewed / Open Access
• [Journal Article] Re-evaluating digestion methods for highly siderophile element and 187Os isotope analysis: Evidence from geological reference materials (2014)
  • Author(s): Ishikawa, A., Senda, R., Suzuki, K., Dale, C. W., Meisel, T.
  • Journal Title: Chemical Geology Volume: 384 Pages: 27-46
  • DOI: 10.1016/j.chemgeo.2014.06.013
  • Peer Reviewed
• [Journal Article] Microstructures, composition, and seismic properties of the Ontong Java Plateau mantle root (2014)
  • Author(s): Tommasi, A., Ishikawa, A.
  • Journal Title: Geochemistry Geophysics Geosystems Volume: 15 Issue: 11 Pages: 4547-4569
  • DOI: 10.1002/2014gc005452
  • Peer Reviewed / Open Access
• [Presentation] Re-Os Isotope and highly siderophile element constraints on the origin of ancient depleted domains in the modern convecting mantle (2016)
  • Author(s): Ishikawa, A., Senda, R. Suzuki, K., Tani, K., Ishii, T.
  • Organizer: Goldschmidt 2016
  • Place of Presentation: パシフィコ横浜 神奈川県横浜市
  • Year and Date: 2016-06-26
  • Int'l Joint Research
• [Presentation] Osmium isotope variations in the Pacific mantle: implications for the distribution of heterogeneity in the convecting mantle (2015)
  • Author(s): Ishikawa, A., Senda, R. Suzuki, K., Tani, K., Ishii, T.
  • Organizer: America Geophysical Union Fall Meeting
  • Place of Presentation: サンフランシスコ アメリカ、カリフォルニア州
  • Year and Date: 2015-12-14
  • Int'l Joint Research / Invited
• [Presentation] 海洋性かんらん岩のオスミウム同位体分布から読むマントルの地球化学的構造とその進化 (2015)
  • Author(s): 石川 晃、仙田量子、鈴木勝彦、谷健一郎、石井輝秋
  • Organizer: 日本地質学会台122年学術大会
  • Place of Presentation: 信州大学長野キャンパス 長野県長野市
  • Year and Date: 2015-09-11
• [Presentation] Osmium isotope heterogeneity in the Pacific mantle: implications for the evolution of convective mantle (2015)
  • Author(s): Ishikawa, A., Senda, R. Suzuki, K., Tani, K., Ishii, T.
  • Organizer: 日本地球惑星科学連合 連合大会 2015年大会
  • Place of Presentation: 幕張メッセ 千葉県千葉市
  • Year and Date: 2015-05-24
• [Presentation] かんらん岩の融解過程に伴う強親鉄性元素の分別作用 (2014)
  • Author(s): 石川晃、仙田量子、谷健一郎、鈴木勝彦、石井輝秋
  • Organizer: 2014年度 日本地球化学会年会
  • Place of Presentation: 富山大学五福キャンパス（富山県、富山市）
  • Year and Date: 2014-09-16 – 2014-09-18
• [Presentation] マントル融解過程に伴う強親鉄性元素の挙動 (2014)
  • Author(s): 石川晃
  • Organizer: 資源地質学会第 64 回年会学術講演会
  • Place of Presentation: 東京大学小柴ホール（東京都、文京区）
  • Year and Date: 2014-06-25 – 2014-06-27
  • Invited
• [Presentation] Osmium isotope heterogeneity in the Pacific uppermost mantle (2014)
  • Author(s): Ishikawa. A., Senda, R., Tani, K., Suzuki, K., Ishii, T.
  • Organizer: Sixth International Orogenic Lherzolite Conference
  • Place of Presentation: Marrakech, Morocco
  • Year and Date: 2014-05-04 – 2014-05-15
• [Presentation] Timing of late veneer on Earth: a siderophile element perspective (2014)
  • Author(s): 石川晃、越田渓子、鈴木勝彦、小宮剛
  • Organizer: 日本地球惑星科学連合 連合大会 2014年大会
  • Place of Presentation: パシフィコ横浜（神奈川県、横浜市）
  • Year and Date: 2014-04-28 – 2014-05-02
• [Presentation] Osmium isotope heterogeneity in the Pacific uppermost mantle (2014)
  • Author(s): A. Ishikawa, R. Senda, K. Tani, K. Suzuki, T. Ishii
  • Organizer: Sixth International Orogenic Lherzolite Conference
  • Place of Presentation: モロッコ マラケシュ
• [Presentation] 太平洋最上部マントルのオスミウム同位体不均質性 (2013)
  • Author(s): 石川 晃、仙田量子、谷健一郎、鈴木勝彦、石井輝秋
  • Organizer: 日本地球化学会第60回年会
  • Place of Presentation: 筑波大学 茨城県つくば市