赣南多期锡成矿作用时代的厘定——来自锡石、黑钨矿U-Pb年代学的证据  

Time constraints for multistage Sn mineralization in southern Jiangxi Province, South China: Evidence from cassiterite and wolframite U-Pb geochronology

作　　者：李伟 唐菊兴[3] 郭娜[2] 宋世伟[4] 吴忠如 郎兴海 鲁捷[1] 连敦梅 LI Wei;TANG JuXing;GUO Na;SONG ShiWei;WU ZhongRu;LANG XingHai;LU Jie;LIAN DunMei(The Seventh Geological Brigade of Jiangxi Bureau of Geology,Key Laboratory of Ionic Rare Earth Resources and Environment,Ganzhou 341000,China;College of Earth and Planetary Sciences,Chengdu University of Technology,Chengdu 610059,China;Chinese Academy of Geological Sciences,State Key Laboratory of Deep Earth and Mineral Exploration,Beijing 100037,China;MNR Key Laboratory for Exploration Theory&Technology of Critical Mineral Resources,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]江西省地质局第七地质大队,自然资源部离子型稀土资源与环境重点实验室,赣州341000 [2]成都理工大学地球与行星科学学院,成都610059 [3]中国地质科学院,深地探测与矿产勘查全国重点实验室,北京100037 [4]中国地质大学(北京),自然资源部战略性金属矿产找矿理论与技术重点实验室,北京100083

出　　处：《岩石学报》2025年第5期1818-1836,共19页Acta Petrologica Sinica

基　　金：江西省地质局青年科技带头人培养项目(2024JXDZKJRC01);国家重点研发计划项目(2021YFC2901702)联合资助详细信息。

摘　　要：锡是赣南的优势矿产之一, 赣南锡成矿作用具有矿床数量多、成矿类型多样等特点。本文选择了坳头、淘锡坑石英脉型锡(钨)矿床和岩背斑岩型锡矿床为研究对象, 开展了锡石和黑钨矿U-Pb同位素研究工作。坳头、淘锡坑、岩背矿床锡石U-Pb年龄分别为228.0±1.5Ma、153.8±0.9Ma、135.9±0.8Ma, 有效约束了赣南印支期、燕山早期和燕山晚期三期锡成矿作用。淘锡坑黑钨矿U-Pb年龄为156.6±3.6Ma, 与锡成矿时代在误差范围内一致, 指示了该矿床空间上具有分带的钨、锡成矿均发生于燕山早期。在典型矿床调查基础上, 结合前人有关锡成矿花岗岩地球化学成果, 认为区内锡矿床形成于碰撞后的伸展环境, 且燕山晚期全面伸展环境诱发了地幔物质的上涌, 更有利于Sn的富集与成矿, 并进一步划分了印支期-燕山早期"南岭式"石英脉型锡(钨)矿床和燕山晚期"武夷式"斑岩型锡矿床。文章提出了赣南东部的陆相火山岩区是锡矿成矿的有利区, 西部崇义-大余-上犹矿集区具印支期锡矿找矿前景。Tin is one of the dominant mineral resources in southern Jiangxi Province, with the characteristics of large number of deposits and diverse metallogenic types. Based on the previous studies, this paper chooses Aotou quartz vein-type Sn deposit, Taoxikeng quartz vein-type W-Sn deposit and Yanbei porphyry Sn deposit as the representatives Sn deposits to study multistage Sn mineralization. Cassiterite grains from Aotou, Taoxikeng, and Yanbei deposits yield Tera-Wasserburg concordia intercept ages of 228.0±1.5Ma, 153.8±0.9Ma and 135.9±0.8Ma, which show three stages of Sn mineralization in this area. Wolframite grains from Taoxikeng W-Sn deposit yield an intercept age of 156.6±3.6Ma, which consistent with the cassiterite U-Pb age within the error range, indicating that the spatial zoning W and Sn mineralization in this deposit were occurred in the same period. The published geochemical data of tin-bearing granites analysis show that Sn deposits were formed in the post-collisional extensional environment, and the overall extensional environment in the Late Yanshanian Period induced the upwelling of mantle materials, which was more conducive to the enrichment and mineralization of Sn. According to the differences in the distribution, geological characteristics and geological background of Sn deposits in southern Jiangxi Province, we divide them into two types: the 'Nanling' Middle-Late Triassic to Late Jurassic quartz vein type Sn (-W) deposits and the 'Wuyi' Early Cretaceous porphyry type Sn deposits. Based on this study, the paper proposes that the continental volcanic rock area in the Wuyishan metallogenic belt is a favorable area for Sn mineralization, and the Chongyi-Shangyou-Dayu ore cluster has a prospecting prospect for the Triassic tin deposits.

关 键 词：锡石U-Pb年龄 黑钨矿U-Pb年龄 成矿时代 矿化类型 赣南 

分 类 号：P597.3[天文地球—地球化学] P618.44[天文地球—地质学]