The large Dabaiyang Au-Te deposit (∼24 t Au), located southwest of the Zhang-Xuan ore district, is mainly hosted in the Neoarchean Sanggan Group. This group, the primary stratigraphic unit in the mining area, is exposed south of the Shangyi-Chongli-Chicheng fault and comprises the Huajiaying and Jiangouhe Formations. The Sanggang Group is the main stratigraphic unit in the mining area and can be divided into the Huajiaying and Jiangouhe Formations. The Huajiaying formation, mainly NW-SE trending in the southwest of ore district, is composed of intensely migmatized granulite, leptynite gneiss, and amphibolite, with key minerals including feldspar, quartz, amphibole, and pyroxene. The Jiangouhe Formation is relatively more extensive, covering over half of the district largely in the northeast. This metamorphic unit consists of weakly migmatized melanocratic metamorphic rocks, such as amphibole plagioclase gneiss, and conformably overlies the underlying Huajiaying Formation.
Ore mineralization is typically characterized by thick quartz veins and disseminated ores. The mineralized quartz veins exhibit two dominant structural trends: a NS strike (∼340°–355°) with gentle dips (0°–30°) and a NW strike (∼293°) with steeper dips (45°–70 %). These veins are generally lens-shaped or tabular, crosscutting the host metamorphic rocks, such as granulite and leptynite gneiss. Their thicknesses range from 1.2 to 2.7 m and average gold grade varies between 3.0 and 5.1 g/t (locally up to ∼ 350 g/t). The mineral paragenesis can be divided into three stages: pre-ore, syn-ore, and post-ore. The pre-ore stage is marked by the formation of K-feldspar as the earliest mineral phase, followed by later quartz. The syn-ore stage includes quartz-sulfide veins and disseminated ores, characterized by abundant quartz associated with sulfides, significant tellurides, and the presence of native gold. The post-ore stage is dominated by quartz and calcite, which typically crosscut or fill fractures in earlier mineralized veins and ores. The results presented here support reclassifying the Dabaiyang deposit as an oxidized intrusion-related gold system , genetically linked to a hidden Late Triassic granitic intrusion.

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