小秦岭华阳川铀铌铅矿床蚀变矿化期次研究  

Mineralization Paragenesis of Huayangchuan U-Nb-Pb Deposit in the Lesser Qinling

作　　者：江宏君 高成 康清清 陈华勇[1] 郑慧 陈冰 董强强 张熊猫 李鹏 李雷 刘宽厚[4] 何世平[4] JIANG Hongjun;GAO Cheng;KANG Qingqing;CHEN Huayong;ZHENG Hui;CHEN Bing;DONG Qiangqiang;ZHANG Xiongmao;LI Peng;LI Lei;LIU Kuanhou;HE Shiping(CAS Key Laboratory of Mineralogy and Metallogeny,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,Guangdong,China;Geological Party No.224,China-Shaanxi Nuclear Industry Group,Xi’an 710100,Shaanxi,China;State Key Laboratory of Nuclear Resource and Environment,East China University of Technology,Nanchang 330013,Jiangxi,China;Xi’an Center of Geological Survey,China Geological Survey,Xi’an 710054,Shaanxi,China)

机构地区：[1]中国科学院广州地球化学研究所矿物学与成矿学重点实验室,广东广州510640 [2]中陕核工业集团二二四大队有限公司,陕西西安710100 [3]东华理工大学核资源与环境国家重点实验室,江西南昌330013 [4]中国地质调查局西安地质调查中心,陕西西安710154

出　　处：《大地构造与成矿学》2020年第3期404-421,共18页Geotectonica et Metallogenia

基　　金：国家重点研发计划重点专项(2017YFC0602200、2017YFC0602205、2017YFC0602300、2017YFC0602304);东华理工大学科研基金项目(DHBK2019310);陕西省创新能力支撑计划青年科技新星项目(2019KJXX-095);中国地质调查局西安地质调查中心科技部专项子项目(0617-1611FZ206);陕西省自然科学研究计划面上基金项目(2016JM4009)联合资助。

摘　　要：华阳川铀铌铅矿床位于华北克拉通南缘小秦岭西段,是一个以铀铌为主,并伴生有铅的超大型综合矿床。根据含矿脉体的穿插关系、蚀变矿物组合及矿物共生关系,将华阳川铀铌铅矿床的成矿过程划分为伟晶岩期、碳酸岩期和碳酸盐化‒硫化物期。伟晶岩期可细分为褐帘石阶段和钾长石‒黑云母‒角闪石化阶段;碳酸岩期可细分为霓辉石‒磁铁矿阶段、角闪石‒榍石‒磷灰石阶段和独居石‒褐帘石阶段;碳酸盐化‒硫化物期可细分为黄铁矿‒磁铁矿化阶段和方铅矿化阶段。铀铌矿化主要发育在伟晶岩期和碳酸岩期,铅矿化主要发育在碳酸盐化‒硫化物期,晚于铀铌矿化形成。其中,伟晶岩期的钾长石‒黑云母‒角闪石组合、碳酸岩期的角闪石‒榍石‒磷灰石组合和独居石‒褐帘石组合为矿区主要的富铀铌矿化组合,可作为富铀矿的找矿标志。结合华阳川含矿钾长石伟晶岩的锆石U-Pb定年研究和前人关于碳酸岩的年代学研究成果,推测华阳川存在两期铀铌成矿作用,分别为1.8 Ga和220 Ma±。The Huayangchuan U-Nb-Pb deposit,located at the western part of the Lesser Qinling in the southern margin of the North China block,is a super-large U-Nb-(Pb)deposit.According to the crosscutting relationships,mineral assemblages and mineral paragenesis,the minerogenesis of the Huayangchuan deposit can be divided into pegmatite period,carbonatite period and carbonate-sulfide period.The pegmatite period can be subdivided into the allanite stage and K-feldspar-biotite-amphibole stage;and the carbonatite period can be subdivided into augite-magnetite stage,amphibole-titanite-apatite stage,and monazite-allanite stage;while the carbonate-sulfide period can be subdivided into pyrite-magnetite stage and galena stage.Uranium and niobium mineralization is mainly developed in the pegmatite and carbonatite periods.Lead mineralization,which postdates uranium and niobium mineralization,mainly occurs in the carbonate-sulfide period.Uranium is mainly enriched in assemblages of K-feldspar-biotite-amphibole,amphibole-titanite-apatite and monazite-allanite,which can be used as prospecting criteria for high grade uranium ores.Combining the zircon U-Pb age of ore-bearing K-feldspar pegmatite as well as the previous chronological results of carbonatites,we inferred that there are two-stages of uranium mineralization in the Huayangchuan deposit,which probably took place at 1.8 Ga and ca.220 Ma,respectively.

关 键 词：小秦岭 华阳川 铀铌铅矿 成矿期次 

分 类 号：P612[天文地球—矿床学]