Geological Features And Ore Prospecting Orientation Of Xinkai Gold Polymetallic Deposit In Lingshou,Hebei Province

The Xinkai Au-polymetallic deposit is located in the Taihangshan tectonomagmatic belt,which is a middle section of the North North China Craton.Au-polymetallic mineralization is closely related to the emplacement of the Mesozoic Mapeng granitoids.Xinkai Au-polymetallic deposit is located in the southeast margin of the Mapeng granitic batholith,and also is adjacented to the large Shihu Au-deposit.Up to now,5 orebodies had been outlined at Xinkai,with 1.2 t Au resource.However,the geological survey in Mining and adjacent areas is still dominated by mineral exploration in the reconnaissance stage,and the degree of geological survey is still low.This study collects the latest mineral exploration results,systematically summarizes the production environment,geological characteristics of the Xinkai Au-polymetallic deposit,and systematically summarizes its mineralization and prospecting direction.Through geological,geochemical,geophysical and remote sensing geological survey,the metallogenic model and prospecting model is Summed up.On this basis,the comprehensive information forecasting method is used to predict mineral resources in the mining area,and the key exploration target areas are pointed out.The mineralization outputted in Mapeng granitoids mainly includes Mo,Cu,Cu,Pb,Zn,Ag and Au,and has longitudinal spatial distribution.Above all,Au±Ag mineralization is mostly located on the southeast margin of the rock mass.Au-polymetallic mineralization is primarily restricted to the NS-trending extension faults and fractures that developed in the inner and the outer contact zones between stocks and adjacent host rocks,and Sb1 and Sb2 are the main ore-bodies.Mineralization mainly contains pyrite,sphalerite,and galena,with minor chalcopyrite.Gangue minerals are primarily silicification,K-feldspar and phyllic zone.Through detailed microscopic identification,gold is mainly natural gold and electrum.The main silver minerals are natural silver,electrum and stromeyerite.Laser probe ⁴⁰Ar-³⁹Ar dating of the auriferous quartz vein yielded the time interval of 155.9¹34.4 Ma,and ore-forming age is Late Jurassic-early cretaceous.Stable isotopes?O-H,S,Pb?indicate that ore-forming fluids may be related to Mesozoic magmatic thermal events.Remote sensing data show that mineralized bodies are mainly located in the secondary faults at the intersection of regional NE-and NW-trending deep faults,Mesozoic vein rocks and metallogenic structures of Au ore-bodies are outputed.The results of gravity gradient and magnetic survey show that the mineralized bodies are mainly located in the negative area of NE-trending gravity gradient belt and the NE-trending magnetic anomaly belt.Geochemical exploration shows that the geochemical anomaly gradient is obvious and the intensity of anomaly is significant.The element combination is Au,Ag,Cu,Pb and Zn,which corresponds to the major metallic minerals.It is further confirmed that Au anomalys are caused by ores,and the concentration maybe indicate the distribution range of the Au ore-bodies.Xinkai Au-polymetallic deposit is closely related to Mesozoic tectono-magmatic thermal events and is controlled by deep and large faults.The ore-froming ore-forming materials of Xinkai Au-polymetallic ore-bodies is mainly derived from Mapeng granite,which is originated in the lower-crust or asthenosphere mantle,and its dynamic mechanism may be related to mantle hot-spot activity?mantle-branch structure?in fuping.In conclusion,it is considered that the Sb1 and Sb2 gold mineralization belts have large prospecting potentials in the southwestern low-resistance advanced anomaly zone and the tendency to extend.