GEOLOGY AND GEOCHEMISTRY OF YUERYA GOLD DEPOSIT
The Yuerya gold deposit is located in Kuanchen country, Hebei province. The main country rocks of it are the Yuerya granite. According to the spatial distributions and forms of orebodies,it could be devided into three ore belts:the south,middle, and north.Major ore mineral is pyrite,and pyrrhotite,chalopyrite,sphalerite,galena, and molybdenite etc.are subordinate. The mineralized type is referred to gold-bearing sulfide-quartz vein.Based on the study of geochemistry of the gold deposit,the author holds that it belongs a typical magmatic-hydrothermal ores,and are possibly derived from "the deep crust. The Co/Ni ratio of pyrite is 1.58;La/Yb ratio of quartz,2.95;total sulfur isotope composition of hydrothermal solution, +2.6‰δOw . + 7.03‰;δD, -88.4‰;δ13C-4.18‰;ore-forming temperature, 305-343℃;nd pH, 6.2 -6.8.Cl-is more than F-,and Na+more than K+ in quartz inclusions,indicating that gold were probably transported as Na[AuCl2],Na[AuCl4],Na[AuS]in the hydrothermal solution.