日本地球惑星科学連合2024年大会

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[J] 口頭発表

セッション記号 H (地球人間圏科学) » H-RE 応用地質学・資源エネルギー利用

[H-RE13] 資源地球科学

2024年5月27日(月) 13:45 〜 15:00 コンベンションホール (CH-A) (幕張メッセ国際会議場)

コンビーナ:大竹 翼(北海道大学大学院工学研究院 環境循環システム部門)、星野 美保子(国立研究開発法人産業技術総合研究所)、高橋 亮平(秋田大学大学院国際資源学研究科)、野崎 達生(国立研究開発法人 海洋研究開発機構 海洋機能利用部門 海底資源センター)、座長:高橋 亮平(秋田大学大学院国際資源学研究科)、星野 美保子(国立研究開発法人産業技術総合研究所)


14:30 〜 14:45

[HRE13-03] タングステン鉱物から製品材料までの高次元化学組成データの次元圧縮によるトレーサビリティ技術の開発

*加藤 湧也1土屋 範芳1ミンダレヴァ ディアナ1松野 哲士1 (1.東北大学環境科学研究科)

キーワード:トレーサビリティ、機械学習、レアアース

In the development of metal resources, illegal mining problems involving environmental issues and human rights violations have arisen, but traceability technology for mineral resource materials that can deal with these problems has not yet been established. In order to establish traceability technology, this study focuses on tungsten, which has limited production areas, and proposes a traceability technology using machine learning to identify intermediate products from the place of origin to industrial products by the patterns of contained elements (impurities). Using machine learning, we aim to develop a traceability technology for metallic materials by identifying the place of origin from the REE (rare earth elements) patterns of tungsten minerals and finally from the elemental patterns of raw materials.
In this study, REEs of two tungsten minerals, Scheelite and Wolframite, from multiple localities were measured by LA-ICP-MS, and 260 published REE pattern data of tungsten minerals (30 localities) were also used. These REE patterns were characterized and identified by unsupervised machine learning (PCA and UMAP) to identify the origin and material.
The REE patterns differ between Scheelite and Wolframite and can be further distinguished using PCA and UMAP. The REE patterns and PCA results varied depending on the mineral type, but there were no significant differences based on provenance, and PCA was unable to identify it. On the other hand, UMAP can classify into different clusters depending on the attribute, and it is considered to have better discrimination performance than PCA.
The REE concentrations in the WC material were ultra-trace (10<ppb) and could not be accurately measured. This suggests that the concentration of REEs decreases during the material manufacturing process. PCA and UMAP were utilized for dimensional compression.
Machine learning (UMAP) for the REE patterns of tungsten minerals and tungsten carbide revealed that the various REE patterns in the mineral stage converge to a certain region during the manufacturing process. This could be applied to traceability of tungsten from mineral production to material manufacturing.