地质学报2024，Vol.98Issue(2)：467-480,14.DOI:10.19762/j.cnki.dizhixuebao.2023020
东昆仑造山带海德乌拉铀矿床成矿流体特征研究
Study on fluid characteristics of the Haidewula uranium deposit,East Kunlun orogenic belt
摘要
Abstract
The Haidewula uranium deposit in the East Kunlun orogenic belt is a newly discovered independent uranium deposit related to volcanic rocks in Northwest China.The discovery of the deposit provides an indication for the exploration of hydrothermal uranium deposits in the East Kunlun orogenic belt.in this paper,the transparent minerals(pink calcite,purple black fluorite and quartz)related to the ore-forming period of the deposit are selected as the research objects.A systematic study of the C-H-O isotopes and fluid inclusions are carried out to find out the source and nature of the ore-forming fluid,and to explore the genesis of the deposit.The results show that the quartz of the ore forming period of the Haidewula uranium deposit is mainly composed of H2O gas-liquid two-phase inclusions,with few CO2-H2O two-phase inclusions;fluid inclusions in calcite vein and fluorite vein contain H2O gas-liquid two-phase inclusions.Pure liquid phase inclusions are occasionally seen,but pure gas phase and solid phase inclusions are not seen in calcite veins.The homogenization temperature range of inclusions in calcite,fluorite and quartz during mineralization is from 133℃ to 187℃(mean 163℃),from 127℃ to 204℃(mean 169℃),and from 183℃ to 287℃(mean 219℃)respectively,and the salinity range is from 1.40％NaCleq to 7.02％NaCleq(mean 3.65％NaCleq),from 0.53％NaCleq to 3.06％NaCleq(mean 1.26％NaCleq),from 7.17％NaCleq to 17.26％NaCleq(mean 11.46％NaCleq).The gas phase composition of fluid inclusions is mainly H2O,and a small amount of CO2.The experimental data of C-H-O isotope show that the variation ranges of δ13 CFluid-V-PDB,δDFluid-V-SMOW,δ18 OFluid-v-smow values are from-1.59‰ to-1.00‰,from-71 ‰ to-63‰,from 0.03‰ to 3.72‰ respectively,indicating that the ore-forming fluid is not a single source,and may be a mixed source of atmospheric precipitation and magmatic water.In addition,the precipitation of pitchblende is mainly due to the changes in physical and chemical conditions caused by the interaction between fluid and hosted-rock,as well as fluid boiling/CO2 degassing,leading to large-scale unloading and precipitation of the pitchblende and other uranium minerals.关键词
火山岩型铀矿床/成矿流体/流体包裹体/激光拉曼光谱/C-H-O同位素Key words
volcanic-hosted uranium deposit/ore-forming fluid/fluid inclusion/laser Raman spectroscopy/C-H-O isotopes引用本文复制引用
朱坤贺,王凯兴,刘晓东,段建华,李彦强,吴佳,余驰达,雷勇亮..东昆仑造山带海德乌拉铀矿床成矿流体特征研究[J].地质学报,2024,98(2):467-480,14.基金项目
本文为国家自然科学基金项目(编号 42072095)、中国核工业集团高校科研攻关项目(编号 201619)、教育厅科技计划项目(编号 GJJ200717)、青海省科技厅重点研发与转化计划"青海省东昆仑火山岩型铀矿资源调查理论创新与找矿突破"(编号 2021-SF-157)和东华理工大学研究生创新基金项目(编号 DHYC-202212)联合资助的成果. （编号 42072095）
