Abstract: The area of the Xiong'ershan – Waifangshan ore field at the southern margin of the North China Craton, Qinling Orogen experienced complex orogenic processes, resulting in prolonged metallogenic intervals during which extensive metal deposits with diverse mineralization types are formed.  Although these complex orogenic processes and related mineralization have been studied extensively, the metallogenic system division and superimposed mineralization are still to be addressed. In this paper, we divide Au and Mo deposits of the Xiong'ershan – Waifangshan ore field into five types, including orogenic, porphyry and magmatic hydrothermal vein molybdenum ore deposit types, and orogenic and magmatic hydrothermal gold ore deposit types. The five types of ore deposits correspond to five kinds of metallogenic systems: (1) Orogenic Mo deposits formed in syn- and post-collision backgrounds during 250 – 227 and 227 – 194 Ma, respectively, from ore forming fluids composed of metamorphic water and crustal Mo; (2) Porphyry Mo deposits formed in subduction and crustal thinning environments during 163 – 135 and 135 –116 Ma, respectively, from magmatic fluids carrying crustal or mantle Mo; (3) Magmatic hydrothermal vein type Mo deposits only formed in post-collision tectonic setting during 227 – 194 Ma from mantle fluid and Mo; (4) Orogenic gold deposits, after pre-mineralization in the Triassic, formed mainly in  subduction environment during 163 – 135 Ma and crustal thinning background during 135 – 103 Ma, from metamorphic water extracted crustal Au; and (5) Magmatic hydrothermal gold deposits only formed in crustal thinning background during 135 – 103 Ma from crustal gold. We also found two kinds of superimposed mineralization: superposition of different mineralizations under either different or same tectonic settings.

Key words: gold and molybdenum ore deposits, metallogenic system, superimposed mineralization, Xiong'ershanfont-size: 14px">– Waifangshan