Over 5000 tonnes of gold were accumulated in the Jiaodong Peninsula at the early Cretaceous, the sources and critical ore-forming processes of which are still controversial. Here, we conducted comprehensive in-situ textural, elemental and isotopic analyses on pyrite and gold grains from the different mineralization styles, hydrothermal stages and depths for three representative gold deposits (Linglong, Xiadian and Jiangjiayao) from the northwestern Jiaodong Peninsula, with the aim to exactly constrain the sources and ore-forming processes. Three groups of d34Spyrite were identified in the studied deposits, of which the Group 1 shows stable and low d34S (4.8-7.6 parts per thousand) throughout the hydrothermal evolution while the Group 2 has elevated d34S (6.0-12.8 parts per thousand) coupled with increasing As and Au concentrations. The Group 3 shows moderate d34S (5.2-9.8 parts per thousand) accompanied by high Al and Si concentrations. The Group 1 suggests a low-d34S primary auriferous fluid derived from a mantle-related source, whereas the Group 2 indicates the primary auriferous fluid leaching additional S, As and Au from the Precambrian metasedimentary rocks along pathway. The Group 3 is petrographically coupled with numerous silicate inclusions, indicat-ing enhanced fluid-rock interaction between the auriferous fluids and the granitic wallrcoks. Gold fine-ness decreases from the early to the late hydrothermal stages, combined with increasing deposition of polymetallic sulfides, suggesting an increase of pH resulting in efficient Au deposition. Gold fineness and Bi concentrations in pyrite decrease with shallowing, suggesting that cooling affected Au deposition as well. Bismuth-Te-S minerals were identified in the deep depths, combined with the well correlated Bi and Ag, implying that Bi-Te complexes might play a role in transporting Au and Ag at high-temperature conditions. The above results corroborate that multiple sources and ore-forming processes were respon-sible for the giant gold mineralization, of which the gold endowment from Precambrian wallrocks needs to be further concerned.(c) 2023 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

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