纳米比亚欢乐谷地区白岗岩型铀矿成矿流体成分与稳定同位素特征

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• 英文论文题名：Ore-forming fluids and stable isotopes geochemistry of alaskite-type uranium deposit in the Gaudeanmus area,Namibia
• 论文作者：陈金勇 ; 范洪海 ; 王生云 ; 顾大钊
• 英文论文作者：CHEN Jin-yong ; FAN Hong-hai ; WANG Sheng-yun ; Gu Da-zhao ; Beijing Research Institute of Uranium Geology ; Key laboratory of Uranium Resource Exploration and Evaluation Technology ; CNNC
• 年：2015
• 作者机构：核工业北京地质研究院;中核铀资源勘查与评价技术重点实验室;
• 论文关键词：成矿流体 ; C-H-O稳定同位素 ; 白岗岩型铀矿 ; 纳米比亚欢乐谷地区
• 英文论文关键词：Ore-forming fluids ; C-H-O stable isotopes geochemistry ; alaskite-type uranium deposit ; Gaudeanmus area ; Namibia
• 会议召开时间：2015-09-21
• 会议录名称：中国核科学技术进展报告（第四卷）——中国核学会2015年学术年会论文集第1册（铀矿地质分卷、铀矿冶分卷）
• 语种：中文
• 分类号：P619.14
• 学会代码：EGVD
• 会议名称：中国核学会2015年学术年会
• 会议地点：中国四川绵阳
• 主办单位：中国核学会
• 学会名称：中国核学会
• 页数：7
• 文件大小：506k
• 原文格式：O
• 会议级别：全国

摘要

本文通过对纳米比亚欢乐谷地区流体包裹体成分和C-H-O稳定同位素的系统研究,厘定了成矿流体的类型及成分,并对该区成矿流体来源及铀的迁移形式进行了初步探讨。研究结果表明,白岗岩型铀矿主成矿期铀主要来源于前达马拉富铀基底,成矿流体阴离子成分以Cl~-、F~-、HCO_3~-和SO_4~(2-)为主,气相成分主要为H_2O和CO_2,铀以铀氧络离子基团(UO_n~(4-2n))和铀的卤化物(UCl_4和UF_4)形式迁移;后期热液主要来自深部流体与大气水的混合,阴离子成分以Cl~-和CO_3~-为主,含少量F~-和SO_4~(2-),气相成分也主要为H_2O和CO_2,铀主要来自之前铀矿物的活化,并以碳酸铀酰络离子(UO_2(CO_3)_2~(2-)和UO_2(CO_3)_3~(4-)迁移。
On the basis of field survey,comparative study of component and C-H-0 stable isotopes geochemistry of fluid inclusions,the authors find out the basic characteristics(temperature,salinity and ingredients etc.) of fluid inclusions of alaskite-type uranium deposit in the Gaudeanmus area,Namibia.And the sources of ore-forming fluids are discussed.The results indicate that uranium mainly comes from the pre-Damaran uranium-rich basement in the main metallogenetic epoch of alaskite-type uranium deposit.Uranium migrates in forms of UO_n~(4-2n),UCl_4 and UF_4.The late hydrothermal fluids are originated from the combination of deep fluids and atmospheric water.Uranium mainly comes from the remobilization of former uranium minerals and is transported in forms of UO_2(CO_3)_2~(2-)and UO_2(CO_3)_3~(4-).

引文

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