Abstract

The study applied correlation network analysis to clarify the relationships among rare earth elements (REEs), uranium (U), and thorium (Th) in rare earth ore samples from the Thèn Thầu – Tả Chu Phùng area (Lai Châu province). A total of 296 primary ore samples and 147 weathered ore samples were analyzed for elemental concentrations using the ICP-MS method. The results show that, in the primary ores, 119 elemental pairs exhibited correlations, including 114 positive and 5 negative correlations; the network density reached 0.78, reflecting a tightly interconnected elemental structure. In the weathered ores, there were 109 correlated elemental pairs (101 positive and 8 negative correlations), with the network density decreasing to 0.71, indicating that the network structure was weakened due to weathering processes.

In the primary ores, elements such as Th, Dy, Er, Y, Gd, and Nd played central roles, reflecting an endogenous origin; Th was the dominant node and served as a geochemical indicator for delineating primary rare earth ore prospects based on primary geochemical anomalies. In the weathered ores, the network structure changed significantly, with elements such as Sm, Eu, Gd, and Sc becoming prominent, and Sc replacing Th as the central element. These elements act as indicators for the exploration of REE mineralization within the weathered crust (secondary ores). U exhibited very low centrality, indicating a strong tendency for dispersion of this element in oxidizing environments.