large- and medium-sized porphyry and porphyry-skarn molybdenum deposit.

The Sigou Mo–W deposit is situated in the southwest area of the Mangling intrusive complex in the NQB, Shaanxi Province. The metal reserves are 0.06 Mt at 0.06% Mo and 0.01 Mt at 0.10% WO3. The exposed rocks belong to the Guangdongping Formation of the Kuanping Group, and they consist of gray mica quartz schist, albite amphibole schist, and marble. A total of 41 industrial ore bodies have been delineated in the Sigou mining area, including 26 molybdenum ore bodies and 15 tungsten ore bodies. These ore bodies are hosted mainly in granite porphyry, cryptoexplosive breccia, marble, and albite amphibole schist, and occur as stratiform bodies. Molybdenum ore bodies are commonly observed in the lower part, primarily located in granite porphyry, cryptoexplosive breccia, and altered wall rocks, whereas tungsten ore bodies are generally identified in the upper part, predominantly hosted in the marble. The Sigou Mo–W deposit is featured by two mineralization types: (1) Disseminated mineralization, which is more common and mainly occurs in granite porphyry (molybdenite), silicified marble (molybdenite), and marble (scheelite); and (2) vein-type mineralization, which is the main mineralization type, commonly occurring as quartz–molybdenite-dominant veins to crosscut cryptoexplosive breccia, granite porphyry, or altered host rocks (molybdenite), and occurs in marble. Four alteration and mineralization stages have been identified: Prograde alteration stage (Stage I), retrograde alteration stage (Stage II), quartz–polymetallic sulfide stage (Stage III), and quartz–calcite stage (Stage IV).

Other Regions, Features and Areas containing this locality

References