Studies on ore genesis of Li deposits and isotopic fractionation by isotope analysis of multi-elements

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K21682
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Petrology/Mineralogy/Economic geology; Earth system and resources engineering
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: ARAOKA DAISUKE 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, 研究員 (60738318)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: リチウム鉱床 / 安定同位体比 / 鉱床成因 / 同位体分別 / 地熱かん水 / リチウム同位体 / マグネシウム同位体 / ストロンチウム同位体

Outline of Final Research Achievements

For rapid purification of multi-elements for stable isotope analysis, I developed new procedure using borate fusion and an ion chromatography system. Then, Li, Mg, and Sr isotopic compositions in water samples from various reservoirs were determined using developed systems, which revealed variations and factors of changes in those isotopic ratios. Finally, these facts were applied to the isotopic compositions in the samples from Li deposits. The results indicated that economically-important ore-forming fluid in the deposits probably had low Li and Mg isotopic compositions due to the water-rock interaction at high temperature condition.

Free Research Field

同位体地球化学、鉱床学

Academic Significance and Societal Importance of the Research Achievements

レアメタルの一つであるLiは二次電池の普及により近年需要が急激に増加している鉱種であり、新たなLi鉱床の探査・開発が重要となっている。今回の結果は、Li鉱床から採取した試料の安定同位体比により、鉱床の有用性がある程度評価できる可能性を示すことができた。今後は採取済みの試料について追加の同位体比分析を行い、上記仮説をさらに検証していく予定である。