世界核地质科学2025，Vol.42Issue(5)：1043-1054,12.DOI:10.3969/j.issn.1672-0636.2025.05.011
库车坳陷卡拉布拉克铀矿点成矿流体的类型与成因
The types and genesis of ore-forming fluids in Karabrak uranium deposit,Kuqa depression,Tarim basin
摘要
Abstract
Karabrak uranium deposit,located in Bozidun area in the western Kuqa depression,experienced strong tectonic movement and deep fluid activity in the late Himalayan tectonic movement.However,the type and genesis of ore-forming fluid in this uranium deposit are still unclear.In this paper,the types and genesis of ore-forming fluids in Karabrak uranium deposit are revealed from the perspectives of inorganic and organic geochemistry,microscopic and macroscopic observation by means of thin section observation,trace elements,fluid inclusions,stable isotopes and scanning electron microscopy.The results show that the Karabrak uranium deposit develops obvious epigenous reduction alteration,and the red rock is reduced to gray-black and gray-green sandstone.A large number of fluid inclusions are observed in quartz particle microfractures of ore-bearing sandstones and sparry calcite cements.The homogenization temperature peaks of fluid inclusions range from 100 to 130℃and 200 to 240℃and the salinity is mainly 8.0 to 12.3%eq.wt%NaCl,indicating that the ore-forming fluids of the Karabrak uranium deposit have the characteristics of medium-low temperature and high salinity.The carbon and oxygen isotopes of calcite cement indicate that the ore-forming fluid of Karabrak uranium deposit is a mixture of low temperature alteration and dehydroxylation of sedimentary organic matter,and the carbon isotopes of carbonate cement are negatively correlated with the uranium content of sandstone.The gray-black and gray-green sandstone of Karabrak uranium deposit develops obvious chloritization and calcification,indicating that the ore-forming fluid is alkaline hydrothermal fluid.Hydrothermal alteration minerals are developed and co-associated with the uranium minerals.Combined with the homogenization temperature of fluid inclusions and vitrinite reflectance of the bitumen,it was believed that alkaline organic thermal fluids with low temperature,high salinity and metalic element actively participated in uranium mineralization in the study area.关键词
库车坳陷/卡拉布拉克铀矿点/成矿流体/流体成因/流体包裹体Key words
Kuqa depression/Karabrak uranium deposit/ore-forming fluid/fluid origin/fluid inclusion分类
天文与地球科学引用本文复制引用
刘念,秦明宽,郭强,许强,张浩..库车坳陷卡拉布拉克铀矿点成矿流体的类型与成因[J].世界核地质科学,2025,42(5):1043-1054,12.基金项目
中核集团研发平台稳定支持科研项目(编号:地YFPT2402)和核工业北京地质研究院自主研发项目(编号:地ZY2504)资助 Supported by the CNNC R&D Platform Project(No.地YFPT2402),the independently developed project of the BRIUG(No.地ZY2504) （编号:地YFPT2402）
