二次イオン質量分析計によるメルト包有物・マントル構成鉱物のマルチ同位体解析

• Project/Area Number: 17740353
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: Petrology/Mineralogy/Science of ore deposit
• Research Institution: Okayama University
• Principal Investigator: 小林 桂 Okayama University, 地球物質科学研究センター, 准教授 (20325129)
• Project Period (FY): 2005 – 2007
• Project Status: Completed (Fiscal Year 2007)
• Budget Amount: ¥3,400,000 (Direct Cost: ¥3,400,000); Fiscal Year 2007: ¥600,000 (Direct Cost: ¥600,000); Fiscal Year 2006: ¥1,300,000 (Direct Cost: ¥1,300,000); Fiscal Year 2005: ¥1,500,000 (Direct Cost: ¥1,500,000)
• Keywords: 高質量分解能二次イオン質量分析計 / リチウム / ホウ素 / 鉛 / アイスランド / ハワイ / メルト包有物 / 同位体

Research Abstract

岡山大学地球物質科学研究センターの高質量分解能二次イオン質量分析言(Cameca ims-1270)は、申請者を中心として運用され、本科学研究費補助金支給期間である平成17〜19年度にわたり大きな研究成果をあげてきた。本年度は、同研究計画の最終年度にあたり、研究期間において作成してきた高精度同位体および微量元素組成に関する標準物質を活用し、天然物質の解析に取り組んできた。とりわけ、玄武岩質ガラスの局所鉛同位体分析法をハワイ火山岩中のオリビンメルト包有物に適用し、詳細な斑晶オリビンの記載と合わせることによって、'鉛同位体の不均質性に関する検討を精力的に行った。この研究成果は現在論文として公表すべく、執筆を進めている。また局所酸素同位体分析に用いる標準物質を、当センターに既設の安定同位体質量分析計(VG PRISM,SIRA12)を用い作成することができた。これを用いた同位体解析にも精力的に取り組む体制が整ったといえる。本科学研究経費支給期間において、リチウム、ホウ素、鉛、酸素同位体の高精度・高確度局所分析が、ガラス試料および、マントル鉱物を中心とした鉱物試料(たとえばオリビンのリチウム同位体組成分析)が確立したことは、今後の応用研究にとっても大きな進歩であるだろう。
さらに、高質量分解能二次イオン質量分析計の1次イオン系に新たなレンズシステムを導入し、同イオン電流量の条件において、従来比約60%のビーム径で分析可能にしたことも技術的に大きな成果であった。これによりさらに高空間分解能分析が可能となり、より局所的な分析へと応用範囲が広がるであろう。

Research Products

• [Journal Article] Generation of Palaeocene Adakitic Andesites by Magma Mixing Yanji area, NE China (2007)
  • Author(s): Guo, F., Nakamura, E., Fan, W., Kobayashi, K., Li C.
  • Journal Title: J. Petrol 48 Pages: 661-692
  • Peer Reviewed
• [Journal Article] Oring of atoll garnets in eclogites and implications for redistribution of trace elements during slab exhumation in a continental subduction zone. (2007)
  • Author(s): Cheng, H., Nakamura, E., Kobayashi, K., zhou, Z.
  • Journal Title: Am. Miner. 92 Pages: 119-129
  • Peer Reviewed
• [Journal Article] Trace element fractionation in deep subduction zones inferred from a lawsonite-eclogite xenolith form the Colorado Plateau (2007)
  • Author(s): Usui, T., Kobayashi, k., Nakamura, E., Helmstaedt, H.
  • Journal Title: Chem. Geol 239 Pages: 336-351
  • Peer Reviewed
• [Journal Article] Sedimentation of isotope atomes in monatomic liquid Se. (2007)
  • Author(s): Mashimo, T., Ono, M., Huang, X., Iguchi, Y., Okayasu, S., Kobayashi, K., Nakamura, E.
  • Journal Title: Appl. Phys. Lett. 91 Pages: 231917-231917
  • Peer Reviewed
• [Journal Article] Lithium isotopic systematice of peridotite xenoliths from Hannuoba, North China Craton; Implications for melt-rock interaction in the considerably thinned lithosphereic mantle. (2007)
  • Author(s): Tang, Y-J., zhang, H-F., Nakamura, E., Moriguti, T., Kobayashi, K., Ying, J-F.
  • Journal Title: Geochim. Cosmochim. Acta. 71 Pages: 4327-4341
  • Peer Reviewed
• [Journal Article] Transformation of Subcontinental Lithospheric Mantle through Peridotite-Melt Reaction; Evidence from a Highly Fertile Mantle Xenolith from the North China Craton. (2007)
  • Author(s): Zhang, H-F., Nakamura, E., Sun, M., Kobayashi, k., Zhang, J., Ying, J-F. Tang, Y-J., Nin, L-F.
  • Journal Title: Int. Geol. Rev. 49 Pages: 658-679
  • Peer Reviewed
• [Journal Article] Generation of Paleocene Adakitic Andesite by Magma Mixing ; Yanji Area, NE China (2007)
  • Author(s): Guo, F., Nakamura, E., Fan, W., Kobyashi, K., Li, C
  • Journal Title: JOURNAL OF PETROLOGY 48 Pages: 661-692
• [Journal Article] Ion microprobe zircon U-Pb dating of the late Archaean metavolcanics and associated granites of the Musoma-Mara Greenstone Belt, Northeast Tanzania : Implications for the geological evolution of the Tanzania Craton (2006)
  • Author(s): Manya S, Kobayashi K, Maboko MAH, Nakamura E
  • Journal Title: JOURNAL OF AFRICAN EARTH SCIENCES 45 Pages: 355-366
• [Journal Article] Geochemical evolution of a shallow magma plumbing system during the last 500 years, Miyakejima volcano, Japan : Constraints from U-238-Th-230-Ra-226 systematics (2006)
  • Author(s): Yokoyama, T., Kuritani, T., Kobayashi, K., Nakamura, E.
  • Journal Title: GEOCHIMICA ET COSMOCHIMICAACTA 70 Pages: 2885-2901
• [Journal Article] In-situ U-Pb SIMS dating and trace element (EPMA) composition of zircon from a granodiorite porphyry in the Wushan copper deposit, China. (2005)
  • Author(s): Ding, X., Jiang, S.-Y., Zhao, K-D., Nakamura, E., Kobayashi, K., Ni, P., Gu, L.-X., Jiang, Y.-H.
  • Journal Title: Mineralogy and Petrology
• [Journal Article] Carbon self-diffusion in a natural diamond (2005)
  • Author(s): Koga, K.T., Walter, M.J., Nakamura, E., Kobayashi, K.
  • Journal Title: Physical Review 72
• [Journal Article] U-Pb zircon dating of regional deformation in the lower crust of the Kohistan arc (2005)
  • Author(s): Yamamoto, H., Kobayashi, K., Nakamura, E., Kaneko, Y., Kausar, A.B.
  • Journal Title: INTERNAT10NAL GEOLOGY REVIEW 4 Pages: 1035-1047
• [Presentation] Phanerozoic crustal growth constrained by zircon U-Pb age and Sr-Nd-Hf isotopic evidence from (2007)
  • Author(s): Amar-Amgalan S, Tanaica R, Kobayashi K, Nakamura E.
  • Organizer: Goldschmidt 2007
  • Place of Presentation: Cologne, Germany
• [Presentation] Large-Scale Fluid Flow in a Cold Subduction-Zone; SIMS Li Isotope Study of Jadeitite Vein in Franciscan Metagraywache (2007)
  • Author(s): Tsujimori, T., Moriguti, T., Kunihiro, T., Kobayashi, K., Nakamura, E.,
  • Organizer: Goldschmidt 2007
  • Place of Presentation: Cologne, Germany
• [Presentation] Tow Late Mesozoic Pulses of Silicic Volcanism within the North Chukotka Area (NE Russia); Magma Sources and Geodynamic Significance. (2007)
  • Author(s): Tikhomirov P., Kalinina, E., Nakamura, E., Kobayashi, K.
  • Organizer: Goldschmidt 2007
  • Place of Presentation: Cologne, Germany
• [Presentation] Geochimical Dynamics in an active Margin of East Asia; Implications from the Temporal and Spacial Geochemical Evolution of Magmatism in Northern Kyushu, SW Japan (2007)
  • Author(s): Tokeshi, S., Kobayashi, K., Makishima, A., Nakamura, E.
  • Organizer: Goldschmidt 2007
  • Place of Presentation: Cologne, Germany
• [Remarks]
  • URL: http://www.misasa.okayama-u.ac.jp/