| JinQingDing gold deposit, the typical quartz vein type gold doposit in the Northeast of Shan dong province, located in the middle of the Muping-Rushan ore-formingbelt, occurs in Mesozoic Kunyunshan monzonitic granite. Ore bodies are controlled by the Jiangjunshi-Quhezhuang tectonic zones of NNE striking faults. According to the genetic mineralogy research of quartz and pyrite, it is discussed, combined with hydrothermal alteration, about the ore genesis, and the prospective prognosis in depth of orebody NO.Ⅱin the JinQingDing gold ore were proposed.The deposit is formed in multi-stage. Ore types in the deep are mainly in veins, Showed a trend of shrinking swollen of the scope and intensity of rock alteration from the surface to the deep. The elements associated with Au are mainly in bringing in during the alteration. Shows the elements associated with ore-forming are mainly brought into by hydrothermal water, not all come from the surrounding rock alteration.The genetic mineralogy research of pyrite shows that the mineralization of pyrite was controlled by the magmatic wate and impacted by the eluviation of ground water. According to the thermoelectric, the mineralization temperature is 130 to 310℃; P% was along the NNE below to the SSW top along the fault showd a regular increasing trend, It's an indirect indicator that the migration of hydrothermal and the Lateral direction of ore were in the same direction. With the mineralogy mapping of thermoelectric properties it is shows that P % and gold grade were all significantly reduced or weakening trend,, indicating the deep downward orebody No.Ⅱmay start to become less below -785m; The electric resistivity of pyrite showed an inverse correlation with an average gold grade,the mineralization intensity and the variation gradient of orebody occurrence; The analytical results of sulfur, lead, helium and argon isotope show that the source of matallogenic materials were mainly from low crust, and the mantle fluids were inwolved in the metallogenic process.The genetic mineralogy research of quartz shows that the homogeneous temperature is between 145~345℃, salinity: 6.35~12.5%, density: 0.80~0.97g/cm3. and ore-forming fluids is moderate to low temperature, low salinity, low density and CO2-rich.The trapping pressure is estimated at least to be 50 to75MPa,and the ore-forming depth ranges from 5.1 to7.0km(6.4km on average).Fluid inclusion analyses show that Na+,Cl-,SO42-,Ca2+,Mg2+ and K+ are main compositions of liquid phase,with minor of NO3-,Al3+ and F-;H2O,CO2 and H2 are dominating in gas phase,with minor of CO,CH4,and N2,and the pH ranges from 4.02 to 4.84(4.53 on average), Eh ranges from 0.68 to﹣0.51(-0.60 on average),lgfO2 ranges from -36.44 to -44.63 and lgfCO2 ranges from -1.11 to -1.75. It is characterized by lower explosive temperature,higher explosive frequency and higher intension of the quartz for the chief metallogenic stages, which is consistent with the Au-rich segments. The curve thermoluminescence of major metallogenic stages analyses show that the Au-rich segments are often characterized by a two-peak pattern, a curve peak location of 230～250℃,a higher peak and a broader half-width, which is as a prospecting criteria.Study on deep Forecast show that: the following of -785m ofⅡorebody has been to the roots of the ore. Tend to pinch down the extension.
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