GEOCHEMICAL CHARACTERISTICS OF THE XIAOTAZIGOU-DONGWUJIAZI GOLD FIELD IN CHAOYANG, LIAONING PROVINCE

The Beidi, Xiaotazigou and Dongwujiazi gold deposits in the Xiaotazigou-Dongwujiazi gold field have different characteristics for their various distances from the intrusion. Research on fluid inclusions of quartz indicates that the Beidi gold deposit at the inner contact zone of the intrusion is formed under moderate temperature and belongs to meso-hydrothermal deposit, while the Xiaotazigou gold deposit at the outer contact zone of the intrusion is mesothermal and moderately-seated, and the Dongwujiazi gold deposit far away from the intrusion is epithermal deposit. Study on oxygen and hydrogen isotopes shows that the ore-forming fluids of the Beidi and Xiaotazigou gold deposits are derived from mainly magmatic water, while those of the Dongwujiazi gold deposit are from the mixed magmatic and atmospheric waters.Trace element evidences suggest that the gold ores from Beidi deposit is featured by enrichment of Mo and Bi, while the Xiaotazigou is enriched with Cu and Zn, and the Dongwujiazi is rich in Pb and Ag. The further the deposit is from the intrusion, the smaller of the Au/Ag ratios of gold-bearing minerals are.