The Study Of The Magma Effect In The Region Of DongUjimqinBanner,Inner Mongolia,and The Metallogenic Relationship Of Tungsten Molybdenum And Molybdenum Deposit

Dongwuqi is located in the northeast of China.Considered with geotectonic,it's located on the eastern Xing-meng orogenic belt.Regional metallogenic position belongs to the greater hinggan mountains Dongwuqi-Nenjiang iron metallogenic provinces in the central and western Cu-Pb-Zn polymetallic mineralization of the southern section of the belt.The metallogenic belt has experienced many tectonic-magmatic effects such as the ancient Asian ocean,the Mongolian-Okhotsk ocean and the ancient Pacific,and provided favorable geological background conditions for polymetallic mineralization?The research area?Dayana area?is located at 15km from Dongwuqi West in Inner Mongolia with an area of about 370km².The overall tectonic pattern of the study area is the Paleozoic uplift and the Cenozoic basin.The Paleozoic uplift is mainly composed of the Devonian Loach and the Carboniferous-Permian Gegen Obo Formation volcanic-sedimentary rocks,with a small amount of Jurassic continental volcanic rocks,and the NEE in the strata develops in a gentle folds or oblique fold Accompanied by a strong Hercynian-Yanshanian granite intrusion.In recent years,the study area has newly discovered the roots of Gegen obo lead-zinc-silver mine,Diana oil tungsten molybdenum ore and Diana gold mine,showing good prospecting prospectThe Gegenaobao lead and zinc ore mine is located in the southeast of the research area and the quartz monzonite is exposed in the deposit,the ore body is produced in the rock mass.In the mining area has been found in the direction of the north to the veins 4,single veins 1 to 3 meters thick,extended 100-500m,Pb + Zn grade 0.5-4.5%,Ag 12-170g/t,belonging to small deposits.Mineral alteration in the mining area includes silicification,carbonation,chlorophyll petrochemical,arsenopyrite,chloritization and sericite,among which the most closely related mineralization is silicification and carbonation,The spatial distribution of rock mass is consistent with that of orebody.The rock mass has a high zinc and sulfur background value and the formation of lead-zinc ores is closely related to the magmatic emplacement activity of quartz monzonite.The deposit belongs to the medium-temperature hydrothermal deposit associated with magmatic action.Dayana tungsten and molybdenum ore is located in the northeastern part of the study area and is located at 4.7km northwest of Gegenaobao Lead-Zinc Mine.In the mining area has been found with black tungsten ore veins 6,molybdenum ore belt more than 10,a single black tungsten ore veins 10-80cm thick,extended 200-500m,WO₃ content of 0.20-7.84%,an average of 0.80%.Has controlled the amount of resources WO₃ 3000 tons,molybdenum molybdenum 8000 tons,molybdenum ore has reached the size of medium-sized deposits.The formation of the deposit is closely related to the biotite granite exposed in the mine.The main wall of the alteration of silicification,greisenization pyrite and other high temperature hydrothermal alteration.The characteristics of fluid inclusions show that the ore-forming temperature of the quartz-molybdenite stage is mainly in the range of 250 ??310 ?,and the ore-forming temperature span in the quartz-tungstenite stage is large,and the temperature is 180 ??320 ? Boiling and temperature drop are the main reasons for the precipitation of tungsten and molybdenum deposits.According to the typical alteration mineral type,inclusions temperature characteristics and mineral assemblage characteristics of ore in the mining area,the Dayana tungsten and molybdenum ore is set as the medium-high temperature hydrothermal deposit.The intrusive rocks in the Diana region dominated by acid rocks.The U-Pb dating of the main rock mass shows that the intrusion age is between 301 and 126 Ma.It shows that there are two magmatic activities in the area,the early magmatic activity is concentrated in 282?300M,the late magmatic activity is concentrated in 126?135Ma.The two magmatic activities are accompanied by two phases of mineralization,respectively,the formation of the Gegenaobao lead-zinc and Dayana tungsten and molybdenumThe quartz monzonite rocks in the Gegenaobao lead-zinc mining area are shown as high-kalcium alkaline series.SiO₂ content is between 60.13%and 66.17%.The trace elements show that the rock mass has heavy and weak rare earth fractionation,with weak negative Eu anomalies.The Hf isotope shows that the rock mass has mantle-derived magma characteristics,and the source area is dominated by depleted mantle,which may infect a small amount of shell material.According to the regional tectonic evolution history and trace element characteristics,it is speculated that the rock mass should be formed in the continental margin arc environment.The Dayana tungsten and molybdenum orefield biotite granite has the characteristics of high silicon,alkali,magnesium and iron,and the K₂O-SiO₂ diagram belongs to the high potassium and alkaline series.The SiO₂ content of the rock mass is between 69.01%and 76.95.The results show that the rock mass has obvious negative Eu anomaly.According to the evolution trend of Sr,Rb,La,Yb,Nb,Ta,Hf and other elements,the rock mass undergoes obvious crystallization differentiation process.The characteristics of I-type granites with high differentiation are very similar to those of China's southern China.Combined with the regional tectonic setting,this paper argues that the Dayana hydrothermal tungsten and molybdenum deposits are formed in the late stage of the paleo-Pacific oblique subduction.In general,the alteration and mineralization types of the study area are well controlled,and they have good ore-controlling geological conditions.The mineralization has many stages of multi-stage and shows good prospecting prospect.