Geology, U-Pb geochronology and stable isotope geochemistry of the Heihaibei gold deposit in the southern part of the Eastern Kunlun Orogenic Belt, China: A granitic intrusion-related gold deposit?

• Gold mineralization occurred in the subduction stage of Early Paleozoic Proto-Tethys ocean, and its age is limited between 454 Ma 439 Ma. H-O-S-Pb-Hf isotopes indicate a magmatic-hydrothermal source, closely related to monzogranites. The Heihaibei gold deposit may instead be classified as granitic intrusion-related deposit. newly discovered southern part Eastern Kunlun Orogenic Belt. Its most distinctive features are that hosted monzogranite, presence pre-ore (possibly syn -ore) monzogranite post-ore gabbro allows constrain mineralization’s formation age. Zircons from monzogranites yield U-Pb ages ± 3 Ma, while zircons separated dikes cutting mineralized body which interpreted minimum Au mineralizing event. Combined with regional geological background, we proposed during ocean. ore assemblage dominated by pyrite, arsenopyrite native gold. hydrothermal alteration has led peculiar enrichment not systematically distributed displays no clear concentric zoning pattern. main formed three stages: K-feldspar-quartz-pyrite (Py1)-arsenopyrite-sericite-epidote (I), quartz-pyrite (Py2)-native gold-chlorite (Ⅱ), quartz-carbonate (III). Ⅱ. Fluid inclusion homogenization temperature salinities decrease I (Th., 268–412 °C; W., 6.87–16.63 wt% NaCl equiv.) Ⅱ 183–288 3.69–14.84 equiv.). δ 18 O δD values (δ H2O = 4.9 9.7‰; V-SMOW -84.1‰ −81.1‰) quartz samples comparable ore-forming fluid possibly underwent fluid-rock interaction Nachitai Group metamorphic rocks early stage. relatively uniform 34 S V-CDT 7.7 8.5‰) slightly elevated compared magmatic values, but could derived magma if significant crustal melt component present. Moreover, within isotopic composition range reservoir, suggesting they probably inherited Pb Hf isotope compositions imply close genetic association magmatism, both products mixing mantle sources. trace element pyrite provide additional evidence was magmatism. Compared typical characteristics orogenic systems (IRGS) deposits,