The giant Baerzhe rare-earth-element–Nb–Zr–Be deposit, Inner Mongolia, China, an Early Cretaceous analogue of the Strange Lake rare-metal deposit, Quebec

作者：Mingqian Wu, Kun‐Feng Qiu, Xi Diao, Jia-Dong Ma, Hao‐Cheng Yu, Maoguo An, Cheng-Long Zhi, Lukáš Krmíček, Deng Jun · 发表于：Geological Society London Special Publications · 年份：2024 · DOI：10.1144/sp551-2023-146 · 被引用次数：5 · 研究领域：Geological and Geochemical Analysis、Geochemistry and Elemental Analysis、earthquake and tectonic studies

The Baerzhe deposit represents world-class mineralization of rare metals, in particular rare earth elements (REEs) and Nb, and shares mineralogical and geochemical similarities with the Strange Lake deposit in Canada. However, the mechanisms responsible for the rare-metal enrichment at Baerzhe are still under debate. Mineralization at Baerzhe is characterized by multiple stages of dissolution, re-precipitation and enrichment of rare-metal elements, as with the Strange Lake deposit. Zirconium was concentrated during magmatic fractionation of elpidite in a transsolvus agpaitic granite (Stage I), and was redistributed into zircon–quartz pseudomorphs during Na-metasomatism (Stage II). Rare earth elements, Nb and Be occur as a variety of mineral assemblages, mainly as pseudomorphs after complete replacement of unknown precursor minerals that are disseminated through the hematized transsolvus granites and were precipitated in three sequential stages (Stages III–V): Stage III is characterized by the mineralization of hingganite, aeschynite-(Y), columbite-(Fe) and euxenite-group minerals, accompanied by hematite alteration; the following Stage IV is defined mainly by monazite-(Ce) crystallization, and Stage V by the preceding REE minerals being replaced by light REE minerals (i.e. bastnäsite-(Ce) and fluocerite-(Ce)). The formation of various pseudomorphs as replacement for precursor minerals is also a common feature documented at Strange Lake. Our results call for a re-evaluation of...