CHEN Qing1, CHEN Yun-jie1*, ZHAO Ru-yi2, WANG Wei1, WANG Gang1, HE Jia-jun1, LI Tao1

(1. Research Institute NO. 203 of nuclear industry, Xian 710000, China;
2. State Key Laboratory of Nuclear Resources and Environment, East China University of Technlogy, Nanchang 330013, China)

Abstract: The C-O isotope analysis of the calcite closely related to the mineralization of the Jibiansi uranium deposit in the eastern section of the Longshoushan metallogenic belt was conducted.The results show that the δCVPDB and δ18OVSMOW values of calcite samples in this study range from -3.8 to +1.4‰, with an average of -1.4‰, and from 17.5‰ to 25.8‰ ,with an average of 23.1‰, respectively. They are basically consistent with those of marine carbonate. Thus, it is inferred that the carbon of calcite in this deposit was mainly derived from the marine carbonate formation of the Precambrian basement. Combined with the analysis of regional geological characteristics, it is believed that the Jinbiansi uranium deposit has the mixed hydrothermal-eluviational genesis. It is suggested that the ore-bearing alteration zone, which had been formed by the early regional alkali-metasomatic hydrothermal mineralization, was then superimposed by the oxidation and leaching of late groundwater to have formed the shallow eluvial type of industrial uranium ore body.

Keywords: C-O isotopoes; genesis of deposit; Calcite; Jibiansi uranium deposit; Longshoushan uranium metallogenic subzone

ACTA MINERALOGICA SINICA Vol. 43, No. 3, 2023, Page 337