Oxidation states of iron and occurrence of ferric iron in olivine at the upper mantle condition

2014 Fiscal Year Final Research Report

• Project/Area Number: 25887040
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Petrology/Mineralogy/Economic geology
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: EJIMA Terumi 独立行政法人産業技術総合研究所, 地圏資源環境研究部門, 研究員 (70712173)
• Project Period (FY): 2013-08-30 – 2015-03-31
• Keywords: かんらん石 / メスバウアー分光分析 / HRTEM / Fe酸化数 / マントルゼノリス

Outline of Final Research Achievements

Several types of mantle xenoliths have been investigated to determined oxidation state of Fe and Fe3+ distribution in olivine at upper mantle condition. The results in the present study indicate that olivine in the mantle xenoliths contains a small amount of Fe3+ and that oxidation state of Fe within olivine in the mantle xenoliths from the upper mantle under the island arc and the continent are 94: 6 and 97: 3, respectively. The fact indicates that the upper mantle under the island arc is in more oxidized condition than that under the continent. This result gives a new view on the redox condition of the upper mantle.

Free Research Field

鉱物学