Metallogenic condition analysis and prospecting direction of sodium metasomatite type uranium in North Qilian

Alkali metasomatite type uranium deposits represent one of the important uranium deposit types in China. The most typical examples are found in the Longshoushan Fault zone and the North Qilian Fold belt within the North Qilian uranium metallogenic area. Representative deposits include the Jiling depositand Xinshuijing deposit (Jiling type) in the Longshoushan area and the biandukou deposit (biandukou type) in the Lenglongling area. Based on comprehensive analysis of regional geology, petrology of sodium metasomatized rocks, the relationship between sodium metasomatism and uranium mineralization, characteristics of uranium mineralization, prospecting criteria, both the Jiling- and biandukou-type uranium deposits are classified assodium metasomatite type uranium deposits. The difference between them is that the former primarily develops in granite, while the latter mainly occurs in sandstone and conglomerate. Our research and analysis suggest that the North Qilian uranium metallogenic area possesses favorable conditions and prospecting direction for alkali (sodium) metasomatite type uranium deposits, which provides criticalt prospecting basis and theoretical guidance for the national search for the discovery of strategic uranium mineral resources.