Genetic models and exploration implication of the paleochannel sandstone-type uranium deposits in the Erlian Basin, North China – A review and comparative study

Abstract

Since the Bayanwula uranium deposit was discovered, several paleochannel sandstone-type uranium deposits have been found in the Manite and Wulanchabu sub-basins of the Erlian Basin. The paleochannel sandstone-type uranium deposits in the Erlian Basin represent important uranium sources in North China. The regional geological settings, depositional facies and sequences, ore-bearing sand bodies and uranium source rocks (e.g., granite and sandstones), play important roles in the formation of these deposits. Three styles of paleochannel sandstone-type uranium deposits occur in the Erlian Basin: 1) interlayer oxidation-style deposit hosted in the braided river sand bodies of the Saihan Formation and characterized by laterally zoned mineralization; 2) phreatic oxidation -style deposits hosted in meandering river sand bodies of the Saihan Formation, showing vertically zoned oxidized mineralization; 3) superimposed mineralization -style deposits hosted in braided river sand bodies of the Saihan Formation, characterized by an oxidized zone from fluvial channel center to margin, which was then overprinted by hydrothermal fluids. These three styles of the uranium deposits depend on depositional microfacies and development of deep-seated faults, which can be used to locate the mineralization and exploration targets within the Erlian Basin.