| Based on the detailed field investigation and previous researches, samples from granitoids , associated with molybdenum (gold) mineralization in Xiong'ershan area, have dated using the zircon SHRIMP(Sensitive High Resolution Ion Microprobe) U-Pb method. Meanwhile, we also dated the molybdenite from the molybdenum deposits by Inductively Coupled Plasma Mass Sperctrometry (ICP-MS), with analytical errors of Re and Os between 0.2-0.3% (2σ). On the basis of the accurately age dating, combined with data on the geology and geochemistry achieved before,the genesis of these granitoids and molybdenum (gold) deposits, and their temporal and spatial relationships have been evaluated. This study provides the first highly precise dating ages of the molybdenum mineralization and rock-forming in Xiong'ershan area. The age of zircon from Wuzhangshan granite stock determined by SHRIMP is156.8±1.2Ma and 130.7±1.4Ma for Huashan stock, and 127.2±1.4Ma for Heyu stock, 157.1±2.9Ma for Nannihu porphyry, and 157.6±2.7Ma for Shangfanggou porphyry and 136.2±1.5Ma for Leimengou granitic porphyry. The results obtained show that the Re-Os model ages are141.8±2.1Ma for Nannihu molybdenum deposit,144.5±2.2 ～145.0±2.2Ma(averaging 145.0±2.2Ma) for the Sandaozhuang deposit, and 143.8±2.1～145.8±2.1Ma(averaging 144.8±2.1Ma) for the Shangfanggou deposit, and a range of 133.1±1.9～131.6±2.0Ma (averaging 132.4±2.0Ma ) for Leimengou deposit. The homogenization temperatures and salinity of the fluid inclusions as well as their He-Ar and S-H-O isotopic components were systematically measured based on 13 samples from the main phase of gold mineralization in the Gongyu gold deposit. The fluid inclusions in the Gongyu mine can be divided into four types, i.e. vapor, vapor-aqueous, aqueous, and CO2-bearing inclusions. The fluid inclusion bubbles are 2-20μm in diameter, mostly in a range of 2-4μm. The homogenization temperatures of the fluid inclusions ranges from 120℃～440℃, mainly in ranges of 150℃～250℃, with three distribution from 150℃～190℃,210℃～250℃and 290 ～350℃. The gold mineralization temperatures vary from 210℃～250℃. Their ice-melting temperatures varies from -2.5℃～-13.5℃, corresponding to a ranges of salinities 4.65wt%～17.26wt% NaCl equivalent. The S-H-O isotopic analytical results show that δ34S values of sulfide are in the range of -1.7‰～2.2‰and close to the value of meteorolite, indicating that the ore-forming substance was probably derived from the upper mantle or some depth. The δD and the δ18OH2O values of the first stage of the main phase of gold mineralization are -68‰～-86‰and -0.6‰～+4.9‰respectively, implying that the ore-forming fluids were derived mainly from the depth. The δD and the δ18OH2O values of the second stage of the main phase gold mineralization are -67‰～-84‰and -0.6‰～-8.9‰respectively, suggesting that the ore-forming fluids probably came from both of the depth and the meteoric water. The Ar-He analytical results show that 3He/4He ratios of fluid inclusions in pyrite are 1.05～3.17R/Ra, 100 times higher than that of the crust and markedly lower than that of the mantle. 40Ar/36Ar ratios are 298～391, slightly higher than that of atmosphere. 40Ar /4He ratios of their corresponding metallogenic fluids are 0.08～0.35 with a mean of 0.20, which are consistent with the value of the crust (0.156). Helium and argon isotope composition of fluid inclusions suggest that the source of ore-forming fluids is mainly meteoric water , and also have some mantle fluids. Therefore, the data above demonstrate that the Gongyu gold deposit is geneticlly related to mantle fluids. In the Qiyugou orefield, although Qiyugou gold deposit (cryptoexplosive breccia type) and Gongyu gold deposit (altered tectonite-type) developed in different types, their fluid inclusions and He-Ar-S-H-O isotopic data show that they originated from the same source and deposited in the same period but at different position, and probably formed in the same metallogenic system which is related to the Yanshanian hydrothermal fluid in Qiyugou orefield. The large-scale Mo(Au) mineralization is a conquerce of the Mesozoic regional tectonic in East China continental. The porphyry Mo and Mo-W deposits are spatial-temporally and genetically related to Mesozoic granite porphyries, Whereas the ore-forming of the gold deposits is more complicated. The emplaced granite intrusions acted as "engines"which drive the mixed hydrothermal solution of the meteorite and mantle fluids to form a conductive circulation system. The hydrothermal solution leached the substance from the Pre-cambrian strata which is proposed the gold source and descharged the gold in some suitable fractures, such as sheer zone to form the gold...
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