地质通报2023，Vol.42Issue(11)：1843-1853,11.DOI:10.12097/j.issn.1671-2552.2023.11.005
大兴安岭西坡二道河子铅锌矿床硫化物Rb-Sr、锆石U-Pb年龄及其对构造背景的制约
Sulfides Rb-Sr and zircon U-Pb ages of the Erdaohezi Pb-Zn deposit in the western slope of the Great Xing'an Range and their constraints on tectonic setting
摘要
Abstract
The Erdaohezi Zn-Pb deposit is located in the middle segment of the Derbugan metallogenic belt in the Erguna block that is on the western slope of the Great Xing'an Range.Rb-Sr dating for sulfides and U-Pb dating for zircons from the andesitic porphyrite were carried out in order to constrain the mineralization age.Three endogenic mineralization stages have been identified,namely a quartz-pyrite stage(Ⅰ),a quartz-polymetallic sulfide stage(Ⅱ),and a quartz-calcite-pyrite stage(Ⅲ),of which,the second stage is the main ore-forming stage.The Rb and Sr contents of 5 sphalerites and 3 pyrites formed at the main mineralization stage in the ore belt Ⅲ vary from 0.081 ×10-6 to 2.632X10-6 and 0.661 ×10-6 to 3.186×10-6,respectively.Accordingly,Rb-Sr isotopic dating of sulfides yields a well-defined isochron age of 140.8±2.3 Ma,close to the zircon U-Pb age(138.8±1.7 Ma)of the andesitic porphyrite crosscutting or parallel to the ore body.The calculated initial 87Sr/86 Sr ratios range from 0.71025 to 0.71205,which is lower than that of the earth's crust,but higher than that of mantle.Combined with the previous studies,we suggest that the Erdaohezi deposit is a hydrothermal-vein deposit and is associated with the andesitic magmatism event(andesitic porphyrite).Additionally,mineralization occurred in an Early Cretaceous extensional setting after the closure of the Mongolia-Okhotsk Ocean.关键词
硫化物/Rb-Sr同位素定年/锆石U-Pb同位素定年/铅锌矿床/二道河子/得尔布干成矿带/大兴安岭Key words
sulfide/Rb-Sr dating/zircon U-Pb dating/Pb-Zn deposit/Erdaohezi/Derbugan metallogenic belt/Great Xing'an Range分类
天文与地球科学引用本文复制引用
刘艳荣,关强兵,张海东,周群君,党顺安..大兴安岭西坡二道河子铅锌矿床硫化物Rb-Sr、锆石U-Pb年龄及其对构造背景的制约[J].地质通报,2023,42(11):1843-1853,11.基金项目
陕西省自然科学基础研究计划项目《黄铁矿原位地球化学对内蒙古甲乌拉矿床两期矿化成因的制约》(编号:2022JM-158)、国家自然科学基金青年基金项目《内蒙古二道河子铅锌(银)矿床硫化物原位微量元素和流体包裹体对矿床成因的制约》(批准号:41702062)、中央高校基本科研业务费专项资金《内蒙古二道河子铅锌(银)矿床硫化物原位S、Pb同位素组成及地质意义》(编号:300102270203) （编号:2022JM-158）
