Genesis of Primitive Crust at the Early History of the Earth
Grant-in-Aid for Overseas Scientific Survey.
|Research Institution||Okayama University|
AKIMOTO Shunーiti Institute for Study of the Earth's Interior, Professor, 地球内部研究センター, 教授 (50013462)
ロバート・ヒル オーストラリア国立大学, 地球科学研究所・リサーチ, フェロー
イアン・キャンベル オーストラリア国立大学, 地球科学研究所・シニア, フェロー
牧嶋 昭夫 岡山大学, 地球内部研究センター, 助手 (70219301)
中村 栄三 岡山大学, 地球内部研究センター, 助手 (80201672)
加々美 寛雄 岡山大学, 地球内部研究センター, 助教授 (20108179)
MAKISHIMA Akio Institute for Study of the Earth's Interior, Research Associate
CAMPBELL Ian The Australian National University Research School of Earth Science, Senior Fell
KAGAMI Hiroo Institute for Study of the Earth's Interior, Assistant Professor
NAKAMURA Eizo Institute for Study of the Earth's Interior, Research Associate
HILL Robert The Australian National University Research School of Earth Science, Research Fe
|Project Fiscal Year
1990 – 1990
Completed(Fiscal Year 1990)
|Budget Amount *help
¥4,300,000 (Direct Cost : ¥4,300,000)
Fiscal Year 1990 : ¥4,300,000 (Direct Cost : ¥4,300,000)
|Keywords||primitive crust / granite / basalt / sedimentary rock / Sm-Nd / La-Ce / SHRIMP / rare earth element / 09isotope dilution mass spectrometric analysis / 10REE partitioning / 初期大陸地殻 / ウラン・鉛年代測定 / 高分解能2次イオン質量分析計 / セリウム同位体比測定 / ランタン・138の壊変定数 / ストロンチウム同位体比測定 / ネオジム同位体比測定 / ホウ素同位体比測定|
The goal of the project is to develop a better understanding of the origin and evolution of the Earth's primitive crust.
Samples of granitic, basaltic and sedimentary rock were collected in the field in Western Australia by the Japanese scientists from the Institute for the Study of the Earth's Interior (ISEI) in collaboration with colleagues from the Research School of Earth Sciences of the Australian National University (RSES) who had already determined ages of 2,700,000,000 years for a variety of rock types from this area.
Aliquots from each sample were returned to ISEI and RSES for further study. A variety of minerals (plagioclase, alkali feldspar, hornblende, biotite, zircon, apatite, titanite and epidote) were separated from three granite samples at RSES for age determinations by the U-Pb method at RSES, and by the Sm-Nd and La-Ce methods at ISEI, and for determination of the partitioning of the rare earth elements (REE) between the different minerals (at ISEI). These samples cover
the two major granitic rock types previously recognized by RSES studies in this area. Ages have been obtained for all three samples using the SHRIMP ion microprobe at RSES, and the Sm-Nd and La-Ce analyses of both rocks and minerals have been completed at ISEI. The ages of rare inherited zircons have also been determined at RSES with the SHRIMP ion microprobe.
Dr Ian Campbell and Dr Robert Hill visited ISEI in March to review the progress of the work to date and to plan the direction of future studies. One exciting outcome of this visit has been the planning of a project to use the SHRIMP ion microprobe to investigate an apparent contradiction in REE partitioning established by the high-precision isotope diluti on mass spectrometric analyses now completed at ISEI. This new project has resulted from the complementarity of the analytical facilities at the two co-operating institutions. This complementarity, and the success of the current project, will serve as the basis for future collaboration between the two institutions. Less
Research Output (12results)