Study on mantle heterogeneity and its origin deduced from halogen composition and chlorine isotope ratio
| Project/Area Number |
16K17842
|
|---|
| Research Category |
Grant-in-Aid for Young Scientists (B)
|
| Allocation Type | Multi-year Fund |
|---|
| Research Field |
Geochemistry/Cosmochemistry
|
|---|
| Research Institution | National Institute of Advanced Industrial Science and Technology (2017-2018)
Japan Agency for Marine-Earth Science and Technology (2016) |
|---|
Principal Investigator |
Toyama Chiaki 国立研究開発法人産業技術総合研究所, 地質調査総合センター, 主任研究員 (30649273)
|
|---|
| Research Collaborator |
KIMURA Jun-Ich
IWAMORI Hikaru
|
|---|
| Project Period (FY) |
2016-04-01 – 2019-03-31
|
| Project Status |
Completed (Fiscal Year 2018)
|
| Budget Amount *help |
¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000)
Fiscal Year 2018: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000)
Fiscal Year 2017: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
|
|---|
| Keywords | 地球化学 / マントル物質 / 地球内部構造 / 塩素同位体 / ハロゲン / 質量分析 / 地殻・マントル物質 / 同位体 / マントル不均質 |
|---|
| Outline of Final Research Achievements |
Halogens are revealed as one of the powerful tracers of water cycling in subduction zones. However, the halogen composition of mantle and pore water are overlapping requiring further constraint. Chlorine has two stable isotopes: 35Cl and 37Cl. Their large relative mass difference suggests that these isotopes should fractionate during reactions between aqueous chloride solutions and solid phases in which Cl is at least partly covalently bound. Thus, the chlorine isotope ratio (δ37Cl) also may provide a good tracer of subducted materials into the mantle. We established and improved the method for high-precision chlorine isotope measurement of mantle derived rock with low chlorine concentration. As a result, the external reproducibility of the δ37Cl measurement was ±0.1 ‰ 2SD. The 37Cl values of Kimberlites were also determined using this method.
|
| Academic Significance and Societal Importance of the Research Achievements |
マントルの組成はさまざまな空間スケールで不均質であることが明らかになってきている。不均質性の広がりと成因については複数のモデルが示されており、一致していない。特に揮発性成分は、試料から失われやすく、現状ではマントル中の分布すら制約に乏しい。本研究はハロゲンのマントル内分布や起源を明らかにするため、新たなツールとして塩素同位体に注目し、その分析手法の検討と実際の試料へ応用を試みたものである。
|
Report
(4 results)
Research Products
(5 results)
