Stratigraphic architecture, sedimentary filling and uranium prospecting of Upper Cretaceous strata, northeastern Songliao Basin

The research on uranium geology in the northern Songliao Basin is relatively weak. Based on the sedimentology, basin analysis and sandstone-type metallogenic theories, the characteristics of sedimentary formation in the Northeast Uplift Zone (NUZ), Songliao Basin, is systematically researched by means of core and well logging. Firstly, the stratigraphic architecture of NUZ and the temporal-spatial distribution of infiltration window for oxygen water with dissolved uranium are clarified. The strata below Nenjiang Formation on the north of Suiling City are overlap structure. Only the Quantou Formation in Hailun Uplift has a truncated-structure at the basin margin, so it has an infiltration window. In contrast, the late Cretaceous strata on the south of Suiling City are all truncated-structure, so all late Cretaceous strata have infiltration windows. Secondly, seven sedimentary facies, including alluvial fan, fan delta, meandering river, braided river, delta, beach bar and semi-deep to deep lake facies, can be recognized. There are different sedimentary filling patterns among Hailun Uplift, Suiling Anticline and Qing'an Uplift. Thirdly, the main exploration formation, prospecting type and prospecting direction of sandstone-hosted uranium deposits in NUZ, Songliao basin, are discussed as follows. The braided channel sand body in the alluvial fan of Quantou Formation in Qing'an area is the most favorable exploration object, followed by the fan delta sand body of Yaojia Formation in Tieli area and the braided channel sand body of Quantou Formation in Hailun area, and finally the delta front sand body of the first Member of Nenjing Formation in Suiling area. This study can provide a new idea for the progress of uranium exploration in NUZ.