Samarium-Neodymium and Rubidium-Strontium isotopic dating of veined REE mineralization for the bayan Obo REE-Nb-Fe deposit, Northern China

Abstract

The Bayan Obo REE-Nb-Fe deposit in Inner Mongolia, China, consists of later REE-mineralizing fluorocarbonate veins cutting the earlier banded and massive ores in the deposit. Samarium-neodymium dating using the minerals including huanghoite and rubidium-strontium dating using single-grain biotites both from the later veins show concordant isochrons corresponding to 442 ± 42 Ma (σs uncertainty) and 459 ± 41 Ma, respectively. The isochron ages suggest that the later REE vein mineralization took place during the middle Paleozoic at Bayan Obo, consistent with geological observations and age data previously reported. © 2009 The Society of Resource Geology.