Genesis and hydrothermal evolution of the Zhazigou skarn W (Mo) deposit, East Qinling, China: Constraints from fluid inclusions and H–O–S–Pb isotopes

•Ore-forming fluids and materials have a dominantly magmatic signature.•Three episodes of fluid ascent from crystallizing magma formed the Zhazigou W (Mo) deposit.•Fluid-rock interactions and fluid boiling are decisive for the scheelite precipitation.•During the W mineralization stage, abundant input of CO2 would decline pH to facilitate scheelite precipitation.