Characteristics of Geology and Geochemistry of the Yinggezhuang Gold Deposit in Eastern Shandong Province

The Yinggezhuang gold deposit is one of the important gold deposits of quartz vein gold type in the Mouping-Rushan gold ore belt of the Jiaodong Peninsula in eastern China.The distribution and occurrence of the gold deposit is controlled by NNE-trending faults.Its wall rock is mainly composed of Archean metamorphic rocks and Kunyushan granite.The gold occurred mainly in beteen minerals(Pyrite and Gangue minerals).The study on fluid inclusion of quartz from gold ore shows that the homogeneous temperature variation has three peak ranges:155℃～165℃,205℃～215℃,and 245℃～215℃.The inclusion salinity of the deposit is relatively low,ranging 1.05～17.17% NaCl.The mineralization pressure ranges from 210 to 580atm,and the metallogenic depth from 0.83 to 2.31km,implying a meso-epi thermal low salinity deposit.Determination of fluid inclusion gredient shows that ore fluid is of the pattern K+-Na+-SO2-4-Cl-.The study result on D-O isotopices shows that the metallogenetic fluid originated from relict magmatic hydrothermal water and metamorphic water mixed with some meteoric water.