Study On Ore Mineral Characteristics And Gold-Silver Occurrence In Dongjun Pb-Zn-Ag Deposit, Inner Mongolia, China

Dongjun Pb-Zn-Ag deposit belongs to Dongwuqi-Xing’an metallogenic belt in Daxing’anling. The tectonic position is located in the E’lunchun late Variscan fold belt of southeastern margin of the Siberia plate. Regional north-eastward De’erbugan deep fault pasts from its northwest. Dongjun deposit is a volcano rock-subvolcano rock hydrothermal type silver lead zinc deposit. In the area with a linear structure, the development of fracture structure, mainly NW and NE two group, ore bodies mainly occur in the Middle Jurassic Tamulan formation in volcano rock, filling in to NE to NW, the tensile fracture, orebody occurrence and structural broken belt line.The purpose of this study is combine the current existing geological prospecting and the mining exploration work. The mainly work is to stuy the characteristics of the ore minerals and gold-silver occurrence, the mainly stuy is the mineralogical characteristics of Dongjun deposit. Provide basic information for the geological exploration, prospecting and evaluation of prospective resources deposits etc. in Dongjun deposit, improve the economic benefits. Obtain the mainly following understanding:1. Dongjun deposit’s ore texture mainly is anhedral-hypidiomorphic granular texture, ore structure mainly are disseminated and stockwork structure, ore minerals mainly are galena; sphalerite and pyrite etc., pulse minerals mainly are quartz and feldspar.2. The S/Fe ratios of pyrite are all>2, belongs to the multi-sulfur type. The Co/Ni ratios varies between0.41～10.47, indicating that Dongjun deposit is the epithermal deposit. Co-Ni-As atom percentage generally fall in or near the skarn-hydrothermal pyrite projection area. Pyrite’s lattice parameter between5.4098×10-10to5.6529×10-10. Galena’s Ag content between405×10-6to3070×10-6, lnSb values between4.44to6.65, Bi content are particularly low, all lower than lppm, the lattice parameter between5.9304×10-10to5.9404×10-10. 3.The independent gold mineral is electrum, and with a low purity in Dongjun deposit. The vast majority of gold’s particle is microscopic. Wrapped gold, inter-granular gold and fissures gold are all visible, wrapped gold maximum and inter-granular gold minimum. Silve output format is independent minerals, mainly are argentite, pyrargyrite, freibergite etc. Silve minerals generally in10μm particle size, silver occurrence mainly is fissures silver, galena is silver’s main carrier minerals.4.The overall average of gold and silver content is not high in Dongjun deposit, gold and silver are associated components. Ore-belt I with a rich silver and gold, ore-belt Ⅱ with a rich silver and a poor gold. Au; Ag and Pb; Zn have a very good correlation. Gold and silver is tend to be rich in the top from the surface to the underground300meter space.