Study On The Alteration Characteristics Of The Badafu Gold Porphyry Copper Deposit In Eastern Tibet

The Bada Copper-Gold deposit is located in the southern part of the Tibetan alkali-rich porphyry belt and is a large copper-gold mine newly discovered in the eastern part of Tibet in recent years.The copper-gold mine is currently under low level of research.At present,there is no explanation for the evolution of ore-forming fluids,its vein characteristics,alteration mineralization types and zoning characteristics,and no alteration types in Bata copper-gold ore.The study of the relationship between finely altered mineral composition and altered clay minerals and mineralization was made.Based on detailed field drilling and short-wave infrared spectroscopy and combined microscopic identification,the geological characteristics and alteration combination zoning of the Bada copper-gold deposit were studied.The Bada deposit is mainly produced in quartz monzonitic porphyry and is locally produced in the contact zone of porphyry and sandstone formations.The wall rock alterations developed by the deposits are mainly shale lithification,potashification,and shale lithification,followed by kaolin petrification,protein petrification,and montmorillonite.The alteration bands are from the inside to the outside: The concentric alteration zones from the inner outward are successively the K-silicate belt,the quartz-sericite belt,and the propylitic belt,the Kaolinite petrochemical belt,the copper-gold ore body mainly exists in the potassium silicate and the porphyry lithology belt,and the copper mineralization is mainly produced in the form of chalcopyrite.Gold mineralization is mainly produced in fine-grained pyrite in the form of silver-gold ore.Copper mineralization is positively correlated with gold mineralization,and the output of ore body is strictly controlled by the northwest-oriented thrust fault.A variety of altered minerals were identified in the Bada mining area using the portable short-wave infrared mineral analyzer(PNIRS).The frequency of occurrence was at least smectite,illite(sericite),kaolinite,dolomite,and green.Minerals such as boulder and Mg-chlorite.The relationship between mineralization intensity and altered mineral composition was found by using infrared spectral data to establish a model.It is initially found that the illite sericite)in the mining area is closely related tomineralization,indicating that the prospecting direction should be found on the sericite + pyrite mineralization zone.This understanding has important guiding significance for the next prospecting work in the mining area.