The Geological Characteristics And Prospecting Prediction Of Nuri Cu-W-Mo Deposit In Eateren Gangdese, Tibet

The Nuriorefield is located on the southern edge of Lhasa block of India and the Asian continent collision zone,and is the tectonic metallogenic mechanism of the continental margin.Deep strike-slip faults and horizontal rotary motion is migration of ore-forming material gathered opens a good ore route,push the closed type conversion fracture for the preservation of the ore-forming fluid provides favorable enclosed ore tectonic conditions.Ore bodies occur mainly in the lower cretaceous bima group of paragraph 4?K₁ b ⁴?,on the whole in between carbonate and clastic rock slope surface,slope interlayer fault zone,shows the layered-bedded,controlled by interlayer slip type detachment fault.Copper of sulfide deposits can be divided into oxidation zone,secondary sulfide enrichment zone and original sulfide ore belt.The host rocks is dominated by skarn,and the ore is mostly veinlets disseminated.Ore mineral mainly in scheelite,chalcopyrite,molybdenite and pyrite,posteriorly for tetrahedrite,in the oxidation zone are also limonite,malachite,cuprite,azurite etc,gangue mineral of garnet,quartz,diopside,epidote,etc.Through the study on the alteration of the borehole,the chlorite and sericite in Nuri orefield are the most developed,followed by the epiphyllite and calcite,and also kaolinite,black mica,montmorillonite and so on.On the whole,with chlorite and sericite as the main alteration combination,with the deepening of the drilling depth,the alteration combination gradually changed into chlorite+epidolite,epidolite+calcite.In the deep part of the borehole,the quartz diorite porphyrite is found to be copper and molybdenum porphyry mineralization,which indicates the possibility of prospecting in the deep part of Nuri orefield.Magma source from the Lhasa block,metallogenic age of 23 to 25 Ma,belongs to the late collision mineralization stage,ore-forming elements from mixed source of crust and mantle,mineralizing fluid in the later mixed with a certain percentage of the atmospheric water.Based on metallogenic geologic and prospecting method study,build up the comprehensive prospecting prediction model,finally confirmed the characteristics of drainage geochemical anomaly and hydrothermal alteration are required.In the end,8minimum prediction workspaces were delineated,among which,there were 2 targets in grade A,3 at B level and 3 at C level.