It is newly discovered and contains more than 30 t Au. The gold ore bodies are mainly hosted in shear structures as auriferous quartz veins and in the upper Devonian Luohansi Formation as disseminated ores. Granite porphyry and dacite porphyry dykes have been recognized in the ore zone. The granite porphyry dykes normally share the same structure as gold ore bodies and are locally mineralized. Dacite porphyry dykes likely intruded later, as they occasionally cut gold ore bodies. The Pangjiahe deposit, located 20 km west of the Matigou deposit.

The Matigou deposit is hosted within the D3l unit, metamorphosed to subgreenschist facies. The local stratigraphy includes volcaniclastic rocks (386 ± 5 Ma, Zircon U-Pb of basalt), quartzite, and argillaceous clastic rocks (with middle to upper Devonian spores) containing interlayers of pyrite-bearing, carbonaceous phyllite. The carbonaceous interlayers (3–50 m thick; containing 0.5–2 vol% pyrite) occur both above and below the main ore bodies. The deposit is hosted within a > 2 km long, NW-striking alteration zone structurally controlled by the Jingshaowan anticline and associated faults. Ore bodies are controlled by secondary structures related to these NW-striking faults. Mineralization occurs both within laminated quartz-pyrite-arsenopyrite veins and in the adjacent phyllitic wall rocks (as foliation-parallel veinlets and disseminations). The main ore zones comprise multiple lenticulars to stratiform ore bodies (average thickness ∼ 4.4 m, average grade ∼ 3.3 g/t Au). Dominant hydrothermal alteration includes silicification, sericitization, sulfidation (pyrite, arsenopyrite), and minor carbonatization, often resulting in bleached wall rocks.

Other Regions, Features and Areas containing this locality

References