CAI Yi1,2, ZHANG Qian1, WANG Da-peng1, LI Kai-wen3, ZHANG Yong-bing1,2
(1. Institute of Geochemistry Chinese Academy of Science, Guiyang 550002, China;
2. University of Chinese Academy of Sciences, Beijing 100049, China;
3. Institute for Ecological Civilization of Karst Area, Guizhou Normal University, Guiyang 550001 Guizhou China;
4. 912 Geological Party of JBEDGMR, Yingtan 335001 Jiangxi China;
5. Henan Institute of Geological Survey, Zhengzhou 450001 Henan China)
Abstract: The Liangjiang Cu deposit, located in the central Guangxi province, southern China, is a typical quartz vein type mineralization. To clarify its ore genesis, an investigation of the geological feature and sulfur and lead isotope is carried out on this deposit. Sulfur isotopic compositions of sulfides have a relatively uniform δ34SCDT value ranging from -1.22‰ to 0.96‰, suggesting a magmatic hydrothermal origin. Ore sulfides from the deposit are enriched in radioactive lead and range in 208Pb/204Pb, 207Pb/204Pb and 206Pb/204Pb ratios from 38.698 to 39.817, 15.773 to 15.879 and 18.307 to 19.232, with the mean values of 39.151, 15.809 and 18.603, respectively. In comparison, they are obviously different from that of Cambrian and Devonian strata and Caledonian magmatic rocks, but consistent with that of the Late Cretaceous magmatic rocks, hinting to that Pb and ore-forming metals are probably derived from the Late Cretaceous magmatism. Field and geochemical evidences, i.e., cross-cutting of ore bodies and magmatic origin of ore-forming materials, indicate that the Cu deposit possibly formed during Late Cretaceous. Regional mineralized features including the Gejiu, Bainiuchang, Dulong and Dachang ore districts suggest that abundant skarn and quartz ore bodies should be probably concealed under cover, indicating a vast prospecting potential at depth in the Liangjiang Cu deposit.
Keywords: Caledonian; mineralization; geochemistry; Yanshannian; Damingshan
Email: enginecai@126.com
ACTA MINERALOGICA SINICA Vol. 36, No. 1, 2016, Page 103-110
