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[Display omitted] • The protolith of Pb-Zn ore hosts is calcareous clastic rocks rather than regional metamorphic rocks. • We first reported the ages of Pb-Zn and Mo ores and their associated intrusion at Fengyan deposit. • Fengyan Pb-Zn and Mo mineralization are space-time and genetically related to granite porphyry. • The ore Mo was derived from a crust-mantle mixed Mo source dominated by crustal input. • A model is proposed to highlight the porphyry Mo and distal Pb-Zn ore system in Central Fujian. Central Fujian is an important Zn-Pb-Ag-Cu-Mo-Au mineral province in southeastern China, yet the polymetallic mineralization is still disputed between Proterozoic volcanogenic massive sulfide (VMS) or Mesozoic skarn type. The Fengyan is representative of the deposit type in central Fujian, characterized by shallow-level stratabound Zn-Pb mineralization and deep-level porphyry Mo mineralization. The ores are mainly hosted by Meso-Neoproterozoic marble and schists. Detailed field investigation, petrographic observation, and electron probe microanalysis indicate that the stratabound Zn-Pb ore host comprises a contact metamorphic/metasomatic suite. LA-ICP-MS zircon U-Pb dating of the granite porphyry yielded a weighted mean 206Pb/238U age of 145.0 ± 1.0 Ma (n = 17, MSWD = 0.97). Hydrothermal titanite grains in the stratabound Pb–Zn ores (intergrown with epidote and galena) yielded a weighted mean 207Pb-corrected 206Pb/238U age of 147.3 ± 4.4 Ma (n = 32, MSWD = 0.45), whilst molybdenite from the concealed Mo orebody has a Re–Os model age of ca. 145.3 to 145.5 Ma. Meanwhile, the molybdenite Re content and the published S-Pb isotope evidence indicate a crust source with minor mantle input. The largely similar age (within error) and ore-material source indicate that the Fengyan mineral system comprises an intrusion-proximal porphyry-type Mo mineralization and intrusion-distal Zn-Pb mineralization. This study proposes a genetic model for the mineral system, which would have important implications for exploring concealed porphyry Mo or Cu-Mo deposits, and/or their related magmatic-hydrothermal systems beneath/beyond these Zn-Pb(-Ag) deposits in central Fujian. [ABSTRACT FROM AUTHOR]

[Display omitted] • Hydrothermal titanite yields a 207Pb-corrected weighted mean U–Pb age of 144 ± 2 Ma. • In situ sulfur isotope compositions of ore sulfides indicate a magmatic source. • The Dingjiashan deposit is a distal stratabound Pb-Zn-Ag skarn deposit. • Hydrothermal titanite is a reliable geochronometer for Pb-Zn-Ag skarn deposits. The Dingjiashan Pb-Zn-Ag deposit is predominantly hosted in the Proterozoic marble and partly in the Jurassic tuff and quartz sandstone in the central Fujian region of southeastern China. Four mineralization stages have been identified: (Ⅰ) prograde skarn (garnet + pyroxene + rhodonite), (Ⅱ) retrograde skarn (epidote + actinolite + tremolite + biotite + chlorite + ilvaite + magnetite + hematite), (III) sulfide assemblage (sphalerite + galena + pyrrhotite + pyrite + chalcopyrite), and (Ⅳ) quartz-calcite assemblage. In this contribution, LA-ICP-MS U-Pb analysis of hydrothermal titanite coexisting with quartz, epidote, biotite, magnetite, and sphalerite in the mineralized sample reveals 207Pb-corrected weighted mean 206Pb/238U age of 144 ± 2 Ma (n = 37, MSWD = 0.86, f 206 < 0.85). In situ sulfur isotope analysis of ore sulfides show a narrow variation of δ34S (-0.7 to + 5.5‰), which is consistent with a magmatic source. The geological, mineralogical, geochronological and in situ sulfur isotopic data collectively imply that the Dingjiashan is a distal stratabound Pb-Zn-Ag skarn deposit. This finding can aid understanding the genesis of other similar polymetallic deposits in the central Fujian region. Our data demonstrates that hydrothermal titanite is a reliable geochronometer for Pb-Zn-Ag skarn deposits and can aid in future prospecting and exploration for concealed porphyry Mo or Cu - Mo deposits that may be present below many of the Pb-Zn-(Ag) deposits in southeastern China. [ABSTRACT FROM AUTHOR]