Geochronology, petrogenesis, and geological significance of the quartz vein-type copper deposits in Longwei area, north-west Dayaoshan, Guangxi

作者：Fu, Song; Li, Shehong^*; Lv, Changxing; Shi, Longqing; Hu, Xuhan; Wu, Jinming; Xie, Zhuolin

来源：Frontiers of Earth Science, 2023.

DOI：10.1007/s11707-022-1013-2

• Re-Os dating
• electron probe
• microanalyser
• quartz-vein copper deposit
• Dayaoshan area

Quartz-vein-type copper deposits were discovered in SN-trend ore-bearing structures in north-west Dayaoshan, Guangxi. Lack of reports on the precise metallogenic age of these deposit has become a bottleneck in metallogenic research in this area. In this study, the quartz vein-type copper mine in Longwei area of Jinxiu was selected as the research object. Fresh illite samples in the fault gouges and ore samples were collected for testing and analysis. Based on the Re-Os isotope dating study, the age of pyrite isochron, belonging to the Caledonian period, was determined to be 417 & PLUSMN; 25 Ma, whereas that of chalcopyrite isochron belonging to the Indosinian period, was found to be 243 & PLUSMN; 18 Ma. Pyrite crystallized considerably earlier than chalcopyrite. The obtained EPMA data were combined with rock mineralogical analysis data, Metasomatous mineral pyrite and metasomatic mineral chalcopyrite were identified to have originated from different hydrothermal systems. In the Indosinian period, copper deposits in the Longwei area underwent pyrite crystallization, pyrite fragmentation, copper-bearing hydrothermal filling, and metasomatism, consolidating and forming minerals. The study determined the mineralisation time and ore sources of copper deposits in the Longwei area. The study provides evidence for the existence of Indosinian hydrothermal activities in the north-western Dayaoshan area.

• 单位
  桂林理工大学