Dataset for manuscript "Paleo-Pacific plate subduction and basement mobilization triggered large-scale formation of Mesozoic gold deposits in the northern margin of the North China Craton"

The northern margin of the North China Craton (NNCC) hosts Mesozoic gold deposits of significant economic importance. The metal sources of these gold systems have long been debated with mainly magmatic-hydrothermal versus orogenic models. Mercury (Hg) isotopes, which undergo unique mass-independent fractionation, can provide important insights into the source of metals in gold deposits due to the close association between Hg and Au in such systems. Here we investigated the Hg isotopic composition of six gold deposits of Middle Jurassic to Lower Cretaceous age and potential source rocks in the NNCC. Variable ∆199Hg values were observed in bulk ore and pyrite samples (-0.28 to 0.34‰, n=51) and coeval granites (-0.21 to 0.13‰; n=25). The negative ∆199Hg values of these samples mostly agree with that observed for metamorphic basement rocks (-0.37 to 0.11‰; n=32). The positive values of these samples agree with that reported in marine sediments (0 to 0.3‰). So the data suggest binary mixing of ocean-recycled Hg from the subducted slab or the metasomatized mantle, and terrestrial-recycled Hg from the Precambrian basement, in Mesozoic gold deposits. The contribution of Hg (and Au, by analogy) from both reservoirs varies dependent on arc versus intracontinental setting and is ultimately controlled by Paleo-Pacific plate subduction and basement mobilization during Mesozoic granite magmatism.