The Bangbu gold mineralization is mainly hosted by Late Triassic carbonaceous and sericitic phyllites, intercalated with metamorphosed sandstone and siltstone. Magmatic activity is limited in the areas of the deposit, with only several small diabase dykes intruded along the faults in the region. The E-W-striking Qusong-Cuogu-Zhemulang brittle-ductile shear zone cuts across the ore district.

Discovered in 2003, the Bangbu gold deposit is situated in the southern region of Gyaca County, within the southeastern part of the Neo-Tethys Indus–Yarlung Tsangpo suture, and represents one of the few large gold deposits (>40 t @ 7.0 g/t) in this belt. The orebody is primarily hosted within the carbonaceous phyllite and sandstone of Songre Formation. A total of 11 faults have been identified within the orefield, predominantly controlled by NW- and NE-trending fault systems. Among these, ore vein III represents the most extensive and economically significant structure, with estimated reserves of up to 16 t and an average grade of 9.4 g/t. The vein is structurally governed by the F7 fault, which trends approximately 339°, with a dip angle ranging from 26° to 45°. The vein spans approximately 600 m in length, 158 m in width, and has an average thickness of 3 m. Alteration in the deposit is only developed along the margins of the orebody, primarily characterized by silicification, sericitization, chloritization, and carbonation. Three metallogenic stages: (I) quartz + coarse-grained pyrite, (II) quartz + fine-grained pyrite + native gold + polymetallic sulfide, and (III) ore-barren calcite.

The Bangbu gold deposit lies near the center of the Qusong-Cuogu-Zhemulang brittle-ductile shear zone, with gold reserves greater than 40 tons and an average grade of 7.0 g/t. The Bangbu gold deposit hosts eight orebodies distributed mainly along the NNW-trending faults. The orebody III is the largest one and contains ∼27.1 tons of gold, with an average Au grade of 9.4 g/t. It has a strike of 218-255° with a dip angle of 26–45° and is about 600 m long and 158 m wide with an average thickness of 3 m. The hydrothermal alterations enveloping the orebodies mainly include silicification, sericitization and chloritization. Three stages of hydrothermal mineralization are identified: (I) almost barren quartz (Qz1) in hooked or lenticular quartz vein, (II) early banded ores with a relatively low Au grade in the outer part of orebody and (III) late massive sulfide ores with a relatively high Au grade near the boundary of orebody and wall rock.

Bangbu is a typical orogenic lode gold deposit in which the ore is confined to auriferous quartz veins.

Other Regions, Features and Areas containing this locality

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