{"title":"Relationship between Pb-Zn and Au mineralization in the Laoyachao deposit, South China: Constraints from geology and S-Pb-He-Ar isotopes","authors":"Jinchuan Huang , Jiantang Peng , Tengxiang Xie , Jiehua Yang","doi":"10.1016/j.jseaes.2024.106190","DOIUrl":null,"url":null,"abstract":"<div><p>Both Pb-Zn and Au mineralization can simultaneously occur at the deposit, camp or regional scale, but their spatial-temporal and genetic relationships have received less attention so far. Here we present detailed field investigations and S-Pb-He-Ar isotope data for the Laoyachao deposit, South China, to interpret the intrinsic associations between Pb-Zn and Au mineralization. Both Pb-Zn and Au ores in the studied area are distributed independently but spatially associated with the same granodiorite. Field and microscopic observations, together with previous dating, show that the Au mineralization postdated the Pb-Zn mineralization. The relatively restricted range and lower δ<sup>34</sup>S values for the Au ores (−0.72 to +0.94 ‰) and the Pb-Zn ores (−1.98 to +2.36 ‰) indicate that both metal mineralization types are attributed to a homogeneous magmatic sulfur source. Lead isotope compositions for the ores and the feldspars from the granodiorites define a well-defined linear array, with the Au ores displaying less radiogenic Pb. In addition, the Pb-Zn ores exhibit lower <sup>3</sup>He/<sup>4</sup>He and <sup>40</sup>Ar/<sup>36</sup>Ar ratios (0.01–0.26 Ra, 298–313) than the Au ores (0.16–2.93 Ra, 341–382). All evidence demonstrated that, besides the granodiorite end-member, an end-member with high-radiogenic Pb and lower <sup>3</sup>He/<sup>4</sup>He values participated in the early Pb-Zn mineralization, in contrast, the other end-member with less radiogenic Pb and higher <sup>3</sup>He/<sup>4</sup>He values was involved in the late Au mineralization. Considering that both Pb-Zn and Au mineralization in the studied deposit are spatially, temporally and genetically related to the same granodiorite, the Pb-Zn mineralization associated with granodiorite can provide an indicator for gold exploration.</p></div>","PeriodicalId":50253,"journal":{"name":"Journal of Asian Earth Sciences","volume":null,"pages":null},"PeriodicalIF":2.7000,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Asian Earth Sciences","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1367912024001858","RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Both Pb-Zn and Au mineralization can simultaneously occur at the deposit, camp or regional scale, but their spatial-temporal and genetic relationships have received less attention so far. Here we present detailed field investigations and S-Pb-He-Ar isotope data for the Laoyachao deposit, South China, to interpret the intrinsic associations between Pb-Zn and Au mineralization. Both Pb-Zn and Au ores in the studied area are distributed independently but spatially associated with the same granodiorite. Field and microscopic observations, together with previous dating, show that the Au mineralization postdated the Pb-Zn mineralization. The relatively restricted range and lower δ34S values for the Au ores (−0.72 to +0.94 ‰) and the Pb-Zn ores (−1.98 to +2.36 ‰) indicate that both metal mineralization types are attributed to a homogeneous magmatic sulfur source. Lead isotope compositions for the ores and the feldspars from the granodiorites define a well-defined linear array, with the Au ores displaying less radiogenic Pb. In addition, the Pb-Zn ores exhibit lower 3He/4He and 40Ar/36Ar ratios (0.01–0.26 Ra, 298–313) than the Au ores (0.16–2.93 Ra, 341–382). All evidence demonstrated that, besides the granodiorite end-member, an end-member with high-radiogenic Pb and lower 3He/4He values participated in the early Pb-Zn mineralization, in contrast, the other end-member with less radiogenic Pb and higher 3He/4He values was involved in the late Au mineralization. Considering that both Pb-Zn and Au mineralization in the studied deposit are spatially, temporally and genetically related to the same granodiorite, the Pb-Zn mineralization associated with granodiorite can provide an indicator for gold exploration.
期刊介绍:
Journal of Asian Earth Sciences has an open access mirror journal Journal of Asian Earth Sciences: X, sharing the same aims and scope, editorial team, submission system and rigorous peer review.
The Journal of Asian Earth Sciences is an international interdisciplinary journal devoted to all aspects of research related to the solid Earth Sciences of Asia. The Journal publishes high quality, peer-reviewed scientific papers on the regional geology, tectonics, geochemistry and geophysics of Asia. It will be devoted primarily to research papers but short communications relating to new developments of broad interest, reviews and book reviews will also be included. Papers must have international appeal and should present work of more than local significance.
The scope includes deep processes of the Asian continent and its adjacent oceans; seismology and earthquakes; orogeny, magmatism, metamorphism and volcanism; growth, deformation and destruction of the Asian crust; crust-mantle interaction; evolution of life (early life, biostratigraphy, biogeography and mass-extinction); fluids, fluxes and reservoirs of mineral and energy resources; surface processes (weathering, erosion, transport and deposition of sediments) and resulting geomorphology; and the response of the Earth to global climate change as viewed within the Asian continent and surrounding oceans.