The Analysis And Research Of Metallogenic Conditions On Sandstone Type Uranium Deposits In Tuanyushan Area,Dachaidan Commission,Qinghai Province

Tuanyushan area is located in the northern margin of Qaidam basin and belongs to the important metallogenic belt of Qin Qikun metallogenic domain.Many Uranium mineralization points(belts)have been found and the resource potential is huge.The focus of this research is on basic research such as the occurrence analysis of uranium source points,development characteristics of interlayer oxidation zone,tectonic feature evolution,radioactive anomalies,other uranium metallogenic conditions,lithology and lithofacies paleofacies,geographical analysis in mining areas.At the same time,combined with the results of previous uranium survey in Tuanyushan area,it can be used as an important basis for the final evaluation of the occurrence characteristics of uranium resources in the study area.Based on the theory of sandstone uranium mineralization,this paper comprehensively collects the geological,geophysical,geochemical,hydrogeological and regional mineral data,the geological data related to coal exploration and development of Tuanyushan area finally determined the direction of prospecting.The prospecting direction should be determined according to the metallogenic conditions and metallogenic rules.Through the comprehensive analysis and study of the relevant geological data,the sedimentary system,the characteristics of stratigraphic structure and the metallogenic geological conditions of uranium deposits in the study area are found out.The formation model of uranium mineralization is summarized and the formation characteristics of uranium resources in the study area are evaluated.Through the effect of the work,combined with the comprehensive analysis of the previous geological and geophysical data in the study area,it is revealed that the Tuanyushan study area has good uranium source conditions and obvious radioactive anomalies in many boreholes.It is clear that the main target horizon for prospecting for sandstone-type uranium deposits is the Shimengou formation of the Middle Jurassic.The formation lithologic assemblage is mainly composed of sand-mud interbeds and has a good"sand-mud sand"formation structure,which provides a favorable basis for the stable migration of ore-bearing fluids.On the whole,the tectonic evolution of the study area shows that the diagenetic period is relatively stable and the ore-forming period is activated,which is also very beneficial to the formation of sandstone-type uranium deposits.At the same time,the target interlayer oxidation zone is generally developed in the study area.The oxidation zone between M2-M4 developed in Shimengou formation and the oxidation zone at the bottom of M5-Shimengou formation are favorable for mineralization in the study area.Therefore,according to this analysis,it is considered that the main target strata in the study area are the Shimengou formation of the Middle Jurassic,and the main research type is the interlayer oxidation zone type,which has the prospecting prospect of sandstone-type uranium deposits.Combined with the abnormal characteristics of drilling development in the area,it is considered that if the thick interlayer oxidation zone developed in the south large-scale recovery area,it is very likely to reveal better industrial uranium deposits.To sum up,Tuanyushan area has favorable geological conditions for sandstone-type uranium mineralization,which is a favorable direction for ore prospecting in the future.