Genesis Analysis Of Yangluozigou Uranium-Molybdenum Deposit In Longhua County

Yangluozigou uranium-molybdenum deposit in Longhua County is located in the northern margin of North China Platform,in Guyuan-Hongshanzi uranium-molybdenum metallogenic belt.Due to the short discovery time of the uranium-molybdenum deposit and the lack of in-depth research on the deposit,this paper relies on the project of ’ Study on the control of Yanshanian intermediate-acid rock mass on the formation of different genetic types of molybdenum deposits in northern Hebei ’.According to the results of rock and ore test and analysis,the source and evolution mechanism of ore-forming materials are determined.Combined with the rock-forming age,regional geological characteristics and tectonic environment of the mining area,the genesis of the deposit is preliminarily determined.Based on the previous research results in the region,it can be seen that the volcanic rocks in the study area are rich in Si,partial to K,and poor in Ca O and Mg O.The comprehensive analysis shows that the mineralization of the Yangluzigou uraniummolybdenum deposit is closely related to the structure,rock mass and stratum.The oreforming materials are mainly derived from the strata of Zhangjiakou Formation(U = 31.5 ×10-6,Mo = 58 × 10-6)and subrhyolite porphyry(U = 36.1 × 10-6,Mo = 521.4 × 10-6)exposed in the area.According to the characteristics of rare earth elements in ore,stratum and rock mass,it can be seen that all of them are enriched in light rare earth elements and depleted in heavy rare earth elements.The characteristics of Eu negative anomaly are considered to be homologous,and through the(La / Yb)N ～ δEu diagram,it is considered that its formation has the characteristics of continental crust transformation.According to the previous analysis of fluid inclusions in the deposit,it is considered that the ore-forming fluid has the characteristics of medium-low temperature and medium-low salinity.The characteristics of hydrogen and oxygen isotopes indicate that the ore-forming fluid is mainly atmospheric precipitation after deep heating.The formation age of Zhangjiakou Formation in the region is 135-138Ma(Late Jurassic),and the formation age of subrhyolite porphyry is about 125-126Ma(Early Cretaceous).The U-Mo mineralization period is in the late Early Cretaceous.After the formation of subrhyolite porphyry,the two are continuous events.The geological characteristics of the deposit are compared with those of Zhangmajing uranium-molybdenum deposit and Madaokou molybdenum deposit in Guyuan-Hongshanzi uranium-molybdenum metallogenic belt,which lays a foundation for clarifying the genesis of uranium-molybdenum deposit in the study area.The determination of genetic types of deposits has guiding significance for the genesis of the same kind of uranium-molybdenum deposits in the regional metallogenic belt.