中国地质2018，Vol.45Issue(3)：544-563,20.DOI:10.12029/gc20180309
延边地区小西南岔富金铜矿床的成矿机理:矿物流体包裹体和同位素的制约
Metallogenic mechanism of the Xiaoxinancha Au-rich Cu deposit in Yanbian area, Jilin Province: Constrains from fluid inclusions and isotope geochemistry
摘要
Abstract
The Xiaoxinancha Au-rich Cu deposit is an important hydrothermal deposit in eastern China. The deposit includes two mines, known as the North mine (veinlet-dissemination type) and the South mine (vein type), which show different ore grades and orebody characteristics. The total homogenization temperatures (Th,total) range from 120 to 470 °C, and the salinities in the Ⅰmineralization stage andⅡ-Ⅲ mineralization stage are 10.1%-20.0%NaCl eqv and 0.4%-45.5%NaCl eqv, respectively, with the gas composition consisting mainly of H2O, CO2, CH4 and N2 in the North mine. The South mine fluids yield Th,total of 150 to 450°C, salinities of 4.0%-11.1%NaCl eqv in theⅠmineralization stage, and the salinities in theⅡ-Ⅲmineralization stage decrease with the decreasing temperatures, and the main gas composition consists of H2O, CO2, and CH4. The quartz-hosted fluid inclusions in the hornblende-granodiorite have homogenization temperatures of 150 to 510°C, and salinities of 4.9%-11.5%NaCl eqv, being similar to those in the North and South mine. The authors hold that the North mine was formed by replacement of fluids which experienced mixing with crustal fluids in the Wudaogou Group after the boiling, whereas the South mine was mainly formed through filling-crystallization of the initial ore-forming fluids with the decreasing temperatures and pressures, and the ore-forming fluids that involved the meteoric water in the mid-late stage produced melnikovite-quartz veins in the North mine and pure sulfide veins in the South mine. The fluid inclusions in the hornblende-granodiorite possibly reveal initial ore-forming fluid signatures characterized by low-moderate salinity and mantle-derived magmatic fluids.关键词
流体演化/成矿机理/小西南岔富金铜矿床/延边地区Key words
fluid evolution/metallogenic mechanism/Xiaoxinancha Au-rich Cu deposit/Yanbian area分类
天文与地球科学引用本文复制引用
门兰静,张馨文,孙景贵,赵俊康,王好均,刘城先..延边地区小西南岔富金铜矿床的成矿机理:矿物流体包裹体和同位素的制约[J].中国地质,2018,45(3):544-563,20.基金项目
吉林省科技厅科研基金项目(120160038,120140075)、吉林省科技发展计划项目(20180101310JC, 20180520086JH)及国家自然科学基金项目(40772052)联合资助.Supported by Science Research Foundation of Jilin Province (No. 120160038, 120140075), Plan Project about the development of Jilin Province Science and Technology (No. 20180101310JC, 20180520086JH) and National Natural Science Foundation of China (No. 40772052). （120160038,120140075）
