Geological Characteristics And Prospecting Direction Of Wudu Gold Deposit In Gansu Province

The Jinkengzi gold mine and the Tangba gold mine are located in the Maqu-Leyang deep fault structural belt.The deep fault structural belt on the southern margin of the West Qinling Mountains,which is held by the three major structural units of the Bikou block,Qinling microplate,and Songpan-Garze structural belt.Sichuan,Shaanxi,Gansu and the Golden Triangle.It is only 30 kilometers away from the Yangshan super-large gold mine in the same structural belt.The ore bodies are produced in veins and clusters in the lower Devonian Qiaotou Formation gray-green chlorite quartz sericite phyllite,gray silty slate,light gray metamorphic sandstone,gray thin-layered micrite limestone,gray medium In the fracture zone of the axis of the compound anticline formed by thick layered silt limestone and other lithologies.The ore-forming material originates from the high-abundance gold strata formed by the early crust-mantle material circulation.The ore-forming fluid belongs to supercritical H2O?CO2?Na Cl fluid with salinity of 2.62?14.32% and density of 0.74?0.99g/cm3.,The main mineralization temperature is about 290?,the pressure is 70 MPa,and the mineralization depth is estimated to be 6.7 kilometers.The ore-forming fluid is mainly magmatic hydrothermal fluid with a small amount of atmospheric precipitation.Gold mainly migrates in the form of Au[HS]2-gold complexes.When it is acidic,it exists in the form of Au HS complexes.There is also part of gold and dioxide.Silicon migrates in the form of colloidal gold.The precipitation and mineralization of gold are related to the hydrothermal cryptoexplosion caused by the dephasing of the ore-forming hydrothermal fluid,and the formation of the ore-bearing fracture structure and the breccia-like hydrothermal dephasing of the ore body.The positioning of the ore body is controlled by the lithology and the low temperature pressure field formed by the regional fault structure.The ore formation occurred after the magmatic activity period caused by the transformation of the geotectonic structure,and was closely related to the magmatic activity.The gold metallogenic depth in this area was very large.A new concealed ore body was discovered at Tangba below 600 meters,from Yangshan to Jinkengzi to Tangba There are three major gold anomalous areas in the region,according to the excellent prospecting prospects.