地质通报2025，Vol.44Issue(4)：601-622,22.DOI:10.12097/gbc.2024.06.027
青海祁漫塔格地区茫崖河东金矿成矿机制:热液磷灰石U-Pb定年及黄铁矿微量元素的制约
Metallogenic mechanism of the Mangyahedong gold deposit in the Qimantage area of Qinghai Province:Constraints from hydrothermal apatite U-Pb dating and trace elements of pyrite
摘要
Abstract
[Objective]The Mangyahedong gold deposit,located in the central Qimantage area of the East Kunlun orogen,is the first discovered orogenic gold deposit with significant exploration potential in the Qimantage region in recent years.The ore bodies are hosted in the volcanic rock series of the Qimantage Group and controlled by NW-trending tectonic fracture zones.However,insufficient research on the genesis of the deposit has hindered further exploration.[Methods]This study conducted systematic microscopic identification,TIMA mineral quantitative analysis,and LA-ICP-MS trace element analysis of pyrite from different mineralization stages.LA-ICP-MS U-Pb dating was performed on hydrothermal apatite associated with main-stage pyrite to constrain the metallogenic timing and discuss the ore-forming mechanisms.[Results]①Three mineralization stages were identified:sericitization(Stage I),carbonate-chlorite-sulfide-native gold(Stage II),and late-stage calcite-pyrite vein formation(Stage III).Electron microprobe analysis and BSE imaging revealed that,in addition to native gold,early-stage As-rich pyrite cores contain relatively higher Au concentrations(0.02%-0.06%,n=8),while pyrite rims are nearly Au-free.Main-stage pyrite exhibits As-poor cores and As-,Au-,Co-enriched intermediate rims.②LA-ICP-MS U-Pb dating of hydrothermal apatite from gold ore yielded a lower intercept age of 406±13 Ma(corrected using 207Pb).[Conclusions]The Mangyahedong gold deposit is classified as an orogenic gold deposit,with mineralization linked to regional metamorphism-deformation processes.The ore-forming materials were derived from the volcanic rock series of the Qimantage Group.关键词
LA-ICP-MS/热液磷灰石U-Pb定年/黄铁矿/微量元素/茫崖河东金矿/祁漫塔格Key words
LA-ICP-MS/U-Pb dating of hydrothermal apatite/pyrite/trace elements/Mangyahedong gold deposit/Qimantage分类
天文与地球科学引用本文复制引用
李少南,马文君,马延宗,杜生鹏,王辉,谢海林,韩玉,魏占浩,陈苏龙,王斌,张得鑫,马海云..青海祁漫塔格地区茫崖河东金矿成矿机制:热液磷灰石U-Pb定年及黄铁矿微量元素的制约[J].地质通报,2025,44(4):601-622,22.基金项目
青海省地勘基金项目《青海省格尔木市茫崖河东地区铜多金属矿普查(2019-2023年度)》(编号:2019048066kc008、2020021077kc044、2021074062kc031、2022012050kc022、2023110003kc003)和第二次青藏高原科学考察研究项目(STEP)《稀贵金属(金、镍、钴、铬铁矿、铂族元素)科学考察与远景评估》(编号:2019QZKK0801-02) （2019-2023年度）
