The Yindongzi-Daxigou strata-bound barite-siderite,silver-polymetallic deposits discovered in the Qinling orogen are hosted within flysch facies in a deep-water fault-controlled basin on the passive northern margin of the Qinling microplate.The orebodies occur in a series of hydrothermal depositonal rocks.Mineralization zoning is characterized by Fe-Ba←Ba-Cu←Pb-Ab→Cu-Ag→Pb→Au.This is obviously a gradational transition mineralization from ventproximal mineralization to more distal mineralization.In this gradational transition between Chefanggou and Yindongzi,vent-proximal mineralization consists of silver-polymetallic orebodies(Pb-Ag),which is the center of hydrothermal mineralization.The Chefanggou Ba-Cu ore district in the west and the Yindongzi Cu-Ag ore district in the east represent vent lateral mineralization.Distal mineralization in the west is represented by the Daxigou Fe-Ba ore district while distal mineralization in te east is represented by the Pb ore district.Thick massive,laminated barren albite chert and jasperite,sometimes with minor silver-ploymetallic mineralization of commercial importance,and pyritization in rocks feature more distal mineralization.Geochemical anomalies of Au-As associations are found in ankerite phyllite and muddy sandstone.Actually,Au deposits are dominantly controlled by the late brittle-ductile shear zone.
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