THE RELATIONSHIP BETWEEN STRUCTURAL-SEDIMENTARY EVOLUTION AND URANIUM MINERALIZATION IN XIERSU DEPRESSION, SOUTHERN SONGLIAO BASIN

The Xiersu depression experienced five stages of structural-sedimentary evolution, i.e. the forming of basement with rich uranium in Early Cretaceous; the forming of coal-bearing rock series in Early Cretaceous; sedimentation of Quantou formation in Late Cretaceous; uranium pre-concentration caused by organic fluid from faults; and uranium deposition by interlayer oxidation. Combined with the sediment characters of covering strata, epigenetic alteration of sandy bodies and discovered uranium occurrences, it is presented that the structural and sedimentary evolution is an important factor for the mineralization of in-situ leachable sandstone type of uranium. The analysis of geological conditions shows a great prospect for uranium deposit in the studied area.