GEOLOGY AND GENESIS OF WANGJIADAGOU GOLD DEPOSIT IN QINGYUAN COUNTY, LIAONING PROVINCE

The small-scaled Wangjiadagou gold deposit, which was discovered in Qingyuan County, Liaoning Province in the end of last century, occurs in the intersection of northeast-trending Hunhe fault and northwest-trending Suzihe fault. The ore-bodies are held by the northwestward structures mostly in Archean Hongtoushan formation. Pyrite is the main gold-bearing mineral. The element of Au commonly presents as independent mineral in three attitudes:being packed, filling in fractures of minerals or crystals, with purity up to 421-595. The gold mineralizing is closely related to the wall rock's silicification and pyrite-sericite-quartz alteration. The mineralization can be divided into four stages, i.e. gold-quartz stage, gold-quartz-pyrite stage, gold-quartz-polymetallic-sulphides stage and gold-quartz-carbonates stage. The δ³⁴S values of pyrites are calculated between 2.13‰ and 6.14‰, indicating that the gold mineralization is tied up with magmatic activities. The homogenization temperature of inclusions in quartz ranges from 149 to 210℃, averagely 182℃, showing its low temperature environment. Considering the close relationship of the gold deposit to the Indosinian felsite dyke (192.5 Ma by K-Ar) and Nankouqian granite (205 Ma, 208 Ma), combining with the regional ore-forming features, the metallogenetic period of Wangjiadagou gold deposit should be defined in Indosinian epoch.