The Zhangquanzhuang gold deposit is a special deposit in the Zhangjiakou district, on the northern margin of the North China Craton. It is characterized by the enrichment of sulfides, the scarcity of tellurides and zero to positive sulfur isotope compositions compared with the famous Dongping and Xiaoyingpan Te-Au-Ag deposit types of the same district. In this paper, we use the in-situ LA-(MC)-ICP-MS and bulk trace element concentrations of pyrite, and in-situ sulfur isotope compositions of sulfides, to study physicochemical conditions and mechanisms of mineral deposition in the Zhangquanzhuang deposit. Pyrite from stage I (PyI) contains high Te contents, pyrite from stage II (PyII) has the highest Co and Ni contents, and pyrite from stage III (PyIII) contains high Cr, Zn, Pb, Ag, Cu, Sb, Bi and Au contents. The calculated in-situ δ³⁴S_H2S values range from 0.9‰ to 6.1‰, and the values for stages I and II are higher than those for stage III. The mineral assemblages and trace element contents in pyrite show that large amounts of metals precipitated during stage III, in which the pH and logfO₂ were constrained within the range of 4.1 to 5.2 and −36.9 to −32.1, respectively. Sulfidation and boiling derived from decreasing pressure may be the main mechanisms leading to mineral deposition in stage III. The Zhangquanzhuang gold deposit was formed in a mineral system that was different from the one that formed the Dongping and Xiaoyingpan Te-Au-Ag deposits, and should thus be called the “Zhangquanzhuang−type” deposit and considered a third gold deposit type in the Zhangjiakou ore field.

The specific source of ancient sedimentary manganese (Mn) deposits is commonly complex. Here we use systematic major and trace element data with strontium (Sr) and neodymium (Nd) isotopic analyses of the Ortokarnash Mn(II) carbonate ores and associated carbonate rocks from the Upper Carboniferous Kalaatehe Formation (ca. 320 Ma) in order to constrain the Mn source. This formation consists of three members: the first member is a volcanic breccia limestone, the second member is a sandy limestone, and the third member is a black marlstone with the Mn(II) carbonate interlayers. Petrographic observations in combination with low Al₂O₃ (<3.0 wt%) and Hf (<0.40 ppm) contents and the lack of correlations between the Al₂O₃ and ⁸⁷Sr/⁸⁶Sr ratios as well as εNd(t) values demonstrate a negligible influence of terrigenous detrital contamination on both Sr and Nd isotopic compositions of the Mn(II) carbonate ores. The Sr isotopes of Mn(II) carbonate ores are most likely affected by post-depositional alteration, while Nd isotopes remain unaltered. The initial ⁸⁷Sr/⁸⁶Sr ratios in the associated carbonate rocks are likely the result of a mixture of the chemical components (i.e., seawater) and the Al-rich components (e.g., volcanoclastic material), while the detrital effects on Nd isotopes are negligible. In addition, both Sr and Nd isotopes in these non-mineralized wall rocks remained unchanged during post-depositional processes. The relatively low Th/Sc ratios and positive εNd(t) values suggest that the aluminosilicate fraction in the calcarenite and sandy limestone was mainly derived from the weathering of a depleted mafic source, representing the riverine input into the seawater. Given that the Mn(II) carbonate ores are characterized by negative εNd(t) values, these suggest that seafloor-vented hydrothermal fluids derived from interaction with the underlying old continental crust mainly contribute to the source of the Mn(II) carbonates.

The Zhilingtou gold deposit in Zhejiang Province, China, is located in the Qin-Hang metallogenic belt and hosted within Paleoproterozoic Badu Group gneiss. Geologic and isotopic analyses reveal that the gold mineralization is associated with a concealed biotite monzogranite (230 ± 1 Ma) and developed along the contact zone with gneiss. Ore-forming fluids, characterized by moderate—high temperatures (237–376°C) and low salinities (1.90–6.72 wt.% NaCl eqv), originated from a magmatic source and were later diluted by meteoric water, leading to gold precipitation. Pb isotopes indicate a crustal origin for lead, closely related to the Badu Group gneiss. The deposit likely formed in a late Triassic postcollisional extensional setting during the Indosinian orogeny involving the South China and North China blocks, suggesting an intrusion-related gold deposit (IRGD) model with excellent potential for further exploration.

This text systematically investigates the Laotudingzi monzogranite (a gold-hosting intrusion) and the Dongbaligou gold ore deposit in the Laoling gold ore belt through comprehensive geochronological, whole-rock geochemical (macroelement and microelement), strontium-neodymium-lead-hafnium isotopic and in situ sulfur-lead isotopic analysis of pyrite, combined with hydrogen-oxygen isotopic studies of hydrothermal quartz. The results demonstrate a significant Early–Middle Jurassic magmatic-mineralization event in southern Jilin Province (Ji’nan). The gold mine is structurally controlled by detachment fractures within the Laoling metamorphic core complex, which developed in an extended environment. The metallogenic materials are primarily derived from adakitic magma, supporting a “decratonic-type” genetic model. By integrating geochronological, geochemical, and isotopic datasets from the ore-related intrusions and gold deposits, as well as fluid inclusion characteristics, we elucidate the metallogenic mechanism linking Jurassic gold mineralization to subduction-related cratonic destruction. The process involved lower crustal thickening induced by Paleo-Pacific Plate subduction, lithospheric destabilization via gravitational foundering and delamination, and syn-extensional magmatism that sourced ore-forming fluids during cratonic lithosphere thinning. This work establishes a genetic framework connecting plate subduction, lithospheric removal, and gold endowment in convergent margin settings.