ハイテク産業に必要なレアメタル資源の地質的背景

抄録

 Worldwide, HREEs are not abundant, but LREEs are. HREEs are limited to certain weathered crust deposits in China where the original granites are rich in HREEs and surface weathering is intense. Because of environmental limitations on mining, it is necessary to discover the primary sources of REEs in alkaline igneous rock provinces. Indium can be recycled easily, and primary sources can be found in Sn-Zn-sulfides deposits of both volcanic and subvolcanic settings. Tungsten and bismuth are also limited mineral resources, but can be found in carbonate rocks with fractionated ilmenite-series granite intrusions. Molybdenum can be supplied sufficiently from porphyry-type deposits.