Quartz samples collected from the Jinman vein copper deposit in the Lanping Basin of western Yunnan were determined by \{\}\+\{40\}Ar/\{\}\+\{39\}Ar fast neutron activation techniques, and the spectra are characterize...Quartz samples collected from the Jinman vein copper deposit in the Lanping Basin of western Yunnan were determined by \{\}\+\{40\}Ar/\{\}\+\{39\}Ar fast neutron activation techniques, and the spectra are characterized as being saddle\|shaped. The samples yielded a plateau age of \{58.05\}±\{0.54\} Ma, a minimum appearance age of \{56.76\}±\{0.81\} Ma and an isochron age of \{54.30\}±\{0.15\} Ma, the three ages being close to each other, indicating that the ages of the quartz samples so far determined are true and reliable. The plateau age represents the time of formation of Cu\|bearing quartz veins, which is corresponding to Early Himalayan. This age is also consistent with the time at which a tectonically thermal event (60 Ma) took place within the Lanping Basin, Yunnan Province. In consideration of the fact that copper ore and other ore types in the vast area of western Yunnan are concentrated mainly in the Early Himalayan strata, the authors believe that there must have existed some indispensable key factors leading to metallogenesis on a large scale during the Early Himalayan period in western Yunnan and also constraining in union the formation of ore deposits there.展开更多
波龙铜矿床是多龙矿集区继多不杂斑岩铜矿床后发现的又一大型斑岩铜矿床。文章在详细的野外地质编录及室内镜下鉴定基础上,对波龙斑岩矿床蚀变与脉体系统进行系统梳理。结果表明,波龙矿床发育明显的蚀变分带,从深部(或核部)往浅部(或外...波龙铜矿床是多龙矿集区继多不杂斑岩铜矿床后发现的又一大型斑岩铜矿床。文章在详细的野外地质编录及室内镜下鉴定基础上,对波龙斑岩矿床蚀变与脉体系统进行系统梳理。结果表明,波龙矿床发育明显的蚀变分带,从深部(或核部)往浅部(或外侧)具有钾化带→黄铁绢英岩化带→泥化叠加黄铁绢英岩化带→角岩化带(或外侧的青磐岩化带)的蚀变分带特征。共识别出M、A、B、D 4种脉体类型,以A、B脉最为发育。与成矿关系密切的主要为钾化带、黄铁绢英岩化带及A、B脉。与国内外典型斑岩矿床蚀变特征相比,波龙矿床蚀变特征总体与"二长岩"模式相似,特征矿物组合与阿根廷Bajo de la Alumbrera矿床,国内驱龙铜矿、多不杂铜矿等都具有相似之处。但波龙矿床从钾化带至黄铁绢英岩化带都大量发育的稀疏-稠密浸染状及脉状磁铁矿是该矿床的独有特色。展开更多
基金ThisresearchprojectwasfinanciallysupportedjointlybythefundsforProject973undertheMajorBasicResearchProgramofthePeople’sRepublicofChina (GrantNo .G19990 4 32 0 8) the 1997"One hundredTopQualifiedPersonnelProgram"sponsoredbytheChineseAcademyofSciencesand
文摘Quartz samples collected from the Jinman vein copper deposit in the Lanping Basin of western Yunnan were determined by \{\}\+\{40\}Ar/\{\}\+\{39\}Ar fast neutron activation techniques, and the spectra are characterized as being saddle\|shaped. The samples yielded a plateau age of \{58.05\}±\{0.54\} Ma, a minimum appearance age of \{56.76\}±\{0.81\} Ma and an isochron age of \{54.30\}±\{0.15\} Ma, the three ages being close to each other, indicating that the ages of the quartz samples so far determined are true and reliable. The plateau age represents the time of formation of Cu\|bearing quartz veins, which is corresponding to Early Himalayan. This age is also consistent with the time at which a tectonically thermal event (60 Ma) took place within the Lanping Basin, Yunnan Province. In consideration of the fact that copper ore and other ore types in the vast area of western Yunnan are concentrated mainly in the Early Himalayan strata, the authors believe that there must have existed some indispensable key factors leading to metallogenesis on a large scale during the Early Himalayan period in western Yunnan and also constraining in union the formation of ore deposits there.
文摘波龙铜矿床是多龙矿集区继多不杂斑岩铜矿床后发现的又一大型斑岩铜矿床。文章在详细的野外地质编录及室内镜下鉴定基础上,对波龙斑岩矿床蚀变与脉体系统进行系统梳理。结果表明,波龙矿床发育明显的蚀变分带,从深部(或核部)往浅部(或外侧)具有钾化带→黄铁绢英岩化带→泥化叠加黄铁绢英岩化带→角岩化带(或外侧的青磐岩化带)的蚀变分带特征。共识别出M、A、B、D 4种脉体类型,以A、B脉最为发育。与成矿关系密切的主要为钾化带、黄铁绢英岩化带及A、B脉。与国内外典型斑岩矿床蚀变特征相比,波龙矿床蚀变特征总体与"二长岩"模式相似,特征矿物组合与阿根廷Bajo de la Alumbrera矿床,国内驱龙铜矿、多不杂铜矿等都具有相似之处。但波龙矿床从钾化带至黄铁绢英岩化带都大量发育的稀疏-稠密浸染状及脉状磁铁矿是该矿床的独有特色。
