青海东昆仑驼路沟钴矿的成矿时代与成因  

Metallogenic timing and genesis of Tuolugou cobalt deposit in eastern Kunlun,Qinghai

作　　者：李小亮 杨乐 张松涛 张万辉 覃泽礼 严正平 赵俊芳 李良[4] LI Xiaoliang;YANG Le;ZHANG Songtao;ZHANG Wanhui;QIN Zeli;YAN Zhengping;ZHAO Junfang;LI Liang(Geological Science and Technology Branch,Qinghai Provincial Non-ferrous Metal Geological and Minerals Exploration Bureau,Xining 810001,China;Qinghai Key Laboratory of Concealed Mineral Exploration,Qinghai Provincial Non-ferrous Metal Geological and Minerals Exploration Bureau,Xining 810007,China;No.1 Geological Exploration Institute,Qinghai Provincial Non-ferrous Metal Geological and Minerals Exploration Bureau,Xining 810007,China;School of Earth Sciences,Yunnan University,Kunming 650500,China)

机构地区：[1]青海省有色地质矿产勘查局地质科技处,西宁810001 [2]青海省有色地质矿产勘查局青海省隐伏矿勘查重点实验室,西宁810007 [3]青海省有色地质矿产勘查局第一地质勘查院,西宁810007 [4]云南大学地球科学学院,昆明530500

出　　处：《世界地质》2022年第3期483-497,共15页World Geology

基　　金：青海省有色地质矿产勘查局局管项目(青色地[2020]63号)。

摘　　要：为确定驼路沟钴矿的成矿时代与成因,利用野外地质调查、锆石U-Pb法定年对含矿建造进行了研究。结果表明,驼路沟钴矿具有同生矿床的特征,发育喷流沉积岩-硅质钠长质岩,矿化以条带状、纹层状及块状构造等同沉积矿石为特征。含矿地层变砾岩的锆石年龄组成非常复杂,跨度大,^(206)Pb/^(238)U年龄介于(469±5)~(3014±26)Ma之间,其中最年轻的一组年龄((469±5)Ma)代表了该变砾岩沉积成岩的时间上限。综合野外地质特征和前人研究成果可知,驼路沟钴矿为一典型的贫硫化物型热水喷流沉积矿床,形成于中—晚奥陶世原特提斯洋板块向万宝沟大洋玄武岩高原北侧俯冲的弧后裂陷环境。To reveal the metallogenic timing and genesis of Tuolugou cobalt deposit,the ore-bearing strata were studied by the methods of geological survey and zircon U-Pb dating in this study.The results show that the Tuolugou cobalt deposit has the features of syngenetic deposit with exhalative sedimentary rock of siliceous albitite,and its mineralization is characterized by the banded,lamellar and massive synsedimentary cobalt ores.The zircon U-Pb data of metaconglomerate from the ore-hosted strata is very complex and spans a wide ^(206)Pb/^(238)U age range of(469±5)to(3014±26)Ma,among which the youngest group of ages((469±5)Ma)defines the maximum age of deposition of the metaconglomerate.Combined with the geological characteristics and previous researches,it can be concluded that the Tuolugou cobalt deposit is a typical sulfide-poor exhalative sedimentary cobalt deposit,formed in a back-arc rift environment where the Proto-Tethys oceanic plate subducted to the north of the Wanbaogou oceanic basalt plateau during middle-late Ordovician.

关 键 词：成矿时代 碎屑锆石 纳赤台群 驼路沟钴矿 喷流沉积型钴矿 

分 类 号：P618.6[天文地球—矿床学]