Mineralization by mantle fluids in the Miaoniuping REE deposit, Sichuan Province, China

The Miaoniuping REE deposit, Sichuan Province, China is the second largest primary LREE deposit which is a little smaller than the world's largest Bayan Obo REE deposit, Inner Mongolia, China. The REE mineralization is spatially and temporally associated with carbonatites and syenites. This deposit is characterized by its tectonic setting of deep faults, the accompanying mantle-derived magmatic activity, the multiple of wall-rock alteration, the moderately high temperature of formation, H2O and CO2 being the important components of the ore-forming fluids, and the mantle source for the ore-forming materials and fluids. These features evidenced that this deposit is the product of the mineralization by mantle fluids.