Fluid evolution and ore genesis of Cu–Pb–Zn veins in the Panjiaduan deposit, Great Xing’an Range, NE China: evidence from fluid inclusion and H–O–He–Ar isotopes

Abstract

The southern Great Xing’an Range (SGXR), located in the eastern segment of the Central Asian Orogenic Belt (CAOB), is one of the most economically important Cu–Mo–Fe–Sn–Pb–Zn–Ag metallogenic provinces in China. The newly discovered Panjiaduan Cu–Pb–Zn deposit (9.3 Mt; at 1.36% Cu, 2.90% Pb, 3.80% Zn and 38.12 g/t Ag), located in the SE segment of the SGXR, is primarily hosted in fracture zones in volcanic rocks and granodiorite of the Manitu Formation. Four paragenetic stages of metallic mineralization are identified: (I) quartz-pyrite-arsenopyrite; (II) quartz-polymetallic sulphide; (III) quartz-galena-sphalerite-argentite; and (IV) quartz-calcite-minor sulphide. The hydrothermal quartz contains three types of primary fluid inclusion (FIs): vapour-rich two-phase liquid-vapour (LV-type), liquid-rich two-phase liquid-vapour (VL-type) and three-phase liquid-vapour-solid FIs (SL-type). Stages I and II contain all types with homogenization temperatures (Th) of 324–386 °C and 276–334 °C as well as salinities of 0.7–38.0 wt% and 0.9–34.7 wt%, respectively, whereas stage III is composed of VL- and LV-type FIs with Th of 210–269 °C and salinities of 0.5–7.2 wt%. Only VL-type FIs occur in stage IV, with Th of 139–185 °C and salinities of 1.6–4.2 wt%. The δ18OH2O and δD values vary from −15.7 to 2.6‰ and −132.7 to −110.2‰, respectively, indicating predominant meteoric water with an initial magmatic source. The He–Ar isotopic compositions of the pyrite inclusions from the Panjiaduan Cu–Pb–Zn veins suggest that fluids were derived from the crust.

Geological characteristics and genesis of the Late Carboniferous extremely thick slate in the Shuangjianzishan Ag-Pb-Zn district, southern Great Xing’an Range, NE China: constraints on metallogenesis and tectonic setting

“…The southern Great Xing'an Range (SGXR), located within the eastern Central Asian Orogenic Belt (CAOB), is one of the most significant Cu-Mo-Fe-Sn-Ag-Pb-Zn metallogenic provinces in China (e.g., Zhou et al, 2010;Zeng et al, 2011;Ouyang et al, 2014a;Ouyang et al, 2014b;Zhai et al, 2014a;Zhai et al, 2014b;Zhai et al, 2017;Zhai et al, 2018;Zhai et al, 2020;Mao et al, 2014;Shu et al, 2016;Chen et al, 2017a;Ke et al, 2017;Gao et al, 2018;Wang et al, 2018;Sun et al, 2022). Research conducted over the past decade on ore deposit geochronology, ore body characteristics, and metallogenic mechanisms reveals that Ag-Pb-Zn deposits in this region formed during the Mesozoic metallogenic episode and are hosted in the Late Paleozoic strata (e.g., Zeng et al, 2011;Yang et al, 2014;Ouyang et al, 2015;Ruan et al, 2015;Liu et al, 2016;Zhai et al, 2020).…”