Abstract: The Wufeng-Wuxingshan gold (silver) deposit in Yanbian area, Jilin Province is a large epithermal gold deposit of low-sulphidation type. The deposit is composed mainly of quartz-calcite veins, quartz veins and veinlet-dissemination sulfide breccias in altered rocks. The mineralization can be divided into four metallogenic stages: pyrite-bearing bulk quartz，chalcedony quartz vein， calcite-quartz vein and calcite-quartz, with the second and third stages being the main ones. The study of the fluid inclusions from the deposit reveals that:(1) most of them are two-phase isolated primary inclusions and chained secondary inclusions along fractures in minerals；(2)homogeneous temperature is mostly 180-280 ℃；(3)the salinity is 4.8 to 7.02 NaCl% and the density is 0.75-0.92 g/cm³；(4)the depth of the mineralization is at 0.15-0.32 km；(5)Laser Raman Spectroscopy analysis of the fluid inclusions reveals their predominant H₂O constitute. These features of the fluid inclusions, combined with hydrogen and oxygen isotope studies (δD is －66‰-－98‰，averaged at －87‰；δ¹⁸O is 3.18‰-－7.2‰ and averaged at －5.1‰), suggest that the ore-forming fluids of the deposit came from the circulating atmospheric waters heated by the deep thermal flow. Under tensile tectonic regime, these hydrothermal fluids migrated through fault zones. Quartz-calcite veins and quartz veins were formed at the upper portion of the Wufeng deposit by filling while the veinlet-dissemination sulfides and breccias were formed at the lower portion of the deposit by fluid boiling. This opinion is different from the previous one that suggested the deposit was formed solely by fluid boiling.

Key words: fluid inclusion, Wufeng-Wuxingshan gold (silver) deposit, Yanbian