Endogentic Metallogenic Systems of Nannihu Mo-W-Cu-Pb-Zn-Ag-Au Ore-Forming Area

Mo-W-Cu-Pb-Zn-Ag-Au metallogenic element association exhibits metallogenic systems of the porphyry type deposit,skarn type deposit and medium-low temperature hydrothermal type deposit.The study of the geochemical characteristics of deposits,the spatial distribution,the stable isotopes and source of ore-forming material has led to the following results:①There are some obvious and complete mineralization belts around the Yanshanian granite.The distribution of commodity and the association of ore-forming elements indicate a geochemical evolutionary series from molybdenum-tungsten polymetals to iron-copper-lead-zinc polymetals to lead-zinc-silver-gold polymetals.②Its minerogenetic epoch has a variation regularity from the earlier Yanshanian to the later Yanshanian,with an obvious decreasing tendency respectively in temperature,salinity and gas-liquid ratio of the ore-forming fluids around the Yanshanian granite.③S,H,O and Pb isotopes show that the metallogenic liquid and material come from magmatic hydrothermal fluids in the Nannihu area.④Hidden magmatic chamber in the earth crust supplies metallogenic substances for Mo-W-Cu-Pb-Zn-Ag-Au metallogenic systems,which can be proved by aeromagnetic anomaly and drill hole data.