Sanhetun Te–Au deposit, Nenjiang County, Heihe, Heilongjiang, Chinai

Regional Level Types
Sanhetun Te–Au deposit	Occurrence
Nenjiang County	County
Heihe	Prefecture
Heilongjiang	Province
China	Country

The ore bodies are primarily located at the structural interfaces between the Lower Cretaceous Jiufengshan Formation and Ganhe Formation, which are composed of volcanogenic-sedimentary rock assemblages, and the Early Carboniferous granitic mylonite. The exposed units in the mining area are mainly of Mesozoic volcanogenic-sedimentary rocks: the Guanghua Formation of the Lower Cretaceous is composed of intermediate to felsic volcanic sedimentary rocks, the Jiufengshan Formation consists of fine clastic sedimentary rocks interbedded with intermediate volcanic rocks, and the Ganhe Formation comprises intermediate-mafic volcanic rocks. The Upper Cretaceous Nenjiang Formation, consisting of mudstone and shale, unconformably overlies the aforementioned stratigraphic units. The intrusive rocks are mainly Early Carboniferous monzogranite and granodiorite, locally subjected to dynamic metamorphism forming mylonite and ultramylonite. The granitic mylonite is crosscut by diorite porphyrite dykes and quartz veins.
Generally, most ore bodies are 1.2 to 4.1 m thick and extend for 150–270 m in a NNE direction (15–25°), dipping to the northwest at moderate angles (40–55°). The gold resource in the Sanhetun deposit is greater than 4 tons, with an average grade of 2.23 to 8.70 g/t. The ores mainly consist of pyrite, which accounts for approximately 90% of the metallic minerals. Five mineralization stages have been identified as follows: the pyrite–quartz stage (I), quartz–pyrite stage (II), gold–telluride–polymetallic sulfide stage (III), telluride–pyrite stage (IV), and carbonate stage (V).

Other Regions, Features and Areas containing this locality

References