| Project/Area Number |
17H02994
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Geochemistry/Cosmochemistry
|
|---|
| Research Institution | Japan Agency for Marine-Earth Science and Technology |
|---|
Principal Investigator |
HANYU Takeshi 国立研究開発法人海洋研究開発機構, 海域地震火山部門(火山・地球内部研究センター), グループリーダー (50359197)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
清水 健二 国立研究開発法人海洋研究開発機構, 超先鋭研究開発部門(高知コア研究所), 技術研究員 (30420491)
山本 順司 北海道大学, 総合博物館, 准教授 (60378536)
|
|---|
| Project Period (FY) |
2017-04-01 – 2020-03-31
|
| Project Status |
Completed (Fiscal Year 2019)
|
| Budget Amount *help |
¥14,950,000 (Direct Cost: ¥11,500,000、Indirect Cost: ¥3,450,000)
Fiscal Year 2019: ¥3,640,000 (Direct Cost: ¥2,800,000、Indirect Cost: ¥840,000)
Fiscal Year 2018: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000)
Fiscal Year 2017: ¥7,410,000 (Direct Cost: ¥5,700,000、Indirect Cost: ¥1,710,000)
|
|---|
| Keywords | 揮発性元素 / マントル / 物質循環 / メルト包有物 / 局所分析 |
|---|
| Outline of Final Research Achievements |
The aim of this project is to understand geochemical cycles of volatiles in the Earth from the studies of mineral-hosted melt inclusions in volcanic rocks derived from the mantle. We established a method to combine several in-situ analytical techniques to measure chemical composition of melt inclusions with the size of 50-100 microns. This method was applied to olivine-hosted melt inclusions in ocean island basalts that are sourced from deep-rooted mantle plumes. We found that those melt inclusions are enriched in Cl in correlation with Pb isotope ratios, suggesting that seawater-derived Cl was transported to the lower mantle by subducted slabs, and thereby the lower mantle involves a mantle domain that preserve significant amount of Cl originated from the Earth’s surface. This is a firm evidence that Cl is cycled between the Earth’s surface and the deep mantle.
|
| Academic Significance and Societal Importance of the Research Achievements |
揮発性成分は地球表層に存在し、生命が育まれるなど地球の進化に重要な役割を果たしている。今回の成果から、地球表層とマントル深部のあいだで塩素が大循環していることが示された。これは水や二酸化炭素など他の揮発性成分も大循環していることを示唆するものであり、固体地球と地球表層の共進化を紐解く今後の研究につながる。また、今回確立した分析手法は火山学にも応用でき、マグマ噴出における揮発性成分の役割を理解する研究にも発展できる。
|
