Geological Characteristics of the Lower Cretaceous Tugulu Group and Uranium Prospecting Direction in the Northwestern Margin of Junggar Basin
Tectonic setting in the northwestern margin of the Junggar has been relatively stable since Late Yanshan period and the delta sedimentary system was developed in the Lower Cretaceous Tugulu Group.In Xiazijie-Delunshan area,thick-layer sand body was deposited in the Member a and Member b of the Tugulu Group.In recent years,the interlayer oxidation zone has been found in the Tugulu Group,which has good uranium metallogenic conditions and prospecting prospects.Guided by the evaluation system of sandstone-type uranium deposits,this paper analyzed the structure,lithology-lithofacies and epigenetic alteration in the study area.It was considered that Delunshan area is the first choice for finding sandstone-type uranium deposits,the main target stratum is the Tugulu Group,and the favorable location for uranium mineralization and prospecting were the place where the interlayer oxidation zone pinch-out and rich organic matter(or pyrite)was developed in the oxidation zone.