Analysis Of Metallogenic Geological Conditions And Prospecting Prediction Of Tungsten Molybdenum Polymetallic Deposits In Yuanbaolinchang Area, Heilongjiang Province

The study area is located in xiaoxing'anling-zhangguangcailing Fe-Pb-Zn-Cu-MoAu-W-Sn crystal pyrite metallogenic beltand the junction of Bindong cu-mo-w-sn-pbzn-fe metallogenic sub belt and Yanshou Pb Zn Cu metallogenic sub belt,where has a good potentiality because of the favourable ore-forming geological conditions and the evident prospecting criteria.Based on the fund projects of Heilongjiang province such as "1:50000 Xinglong Town,Yangjiadian,Yuanbao Town,administrative village scale regional geological and mineral survey" and "general survey of tungsten polymetallic deposits in Yuanbao forest farm,Shangzhi City,Heilongjiang Province",the characteristics of tungsten,molybdenum and silver mineralization and prospecting indicators in the study area are summarized on the basis of collecting and sorting out the previous research results,and the metallogenic enrichment and genesis of the deposit are discussed,The prospecting model is established and the research on prospecting prediction is carried out.The recognition and progress we have made are as follows.Focusing on Shuangyashan tungsten molybdenum polymetallic deposit,the metallogenic characteristics of tungsten molybdenum polymetallic deposit are summarized.In the study area,tungsten mineralization occurs gin the quartz veins containing wolframite in the structure belt of medium grain porphyritic granodiorite,and the wall rock alteration mainly includes dolomitization,chloritization and potassification,which belongs to the vein type mineralization of high temperature hydrothermal filling;molybdenum mineralization occurs in the structural fracture of monzogranite,which has the characteristics of veinlet disseminated mineralization,and the wall rock alteration includes silicification,potassification and chloritization,etc.The variation zone is obviously characterized by hydrothermal solution-porphyry genesis;silver mineralization occurs in adamellite,outside of tungsten molybdenum mineralization,and wall rock alteration is characterized by sericitization,chloritization,kaolinization with the characteristics of medium and low temperature hydrothermal filling vein type deposit.It is considered that the Late Triassic early Jurassic granodiorite,monzogranite and fault structure control the mineralization of tungsten molybdenum polymetallic and the distribution of ore bodies,which constitute the main metallogenic geological conditions.Granodiorite is the host rock of tungsten ore,and monzonitic granite is the host rock of molybdenum ore and silver ore.The ore body shape,occurrence and spatial distribution are controlled by NE trending fault structure.The distribution of W-Mo polymetallic mineralization is controlled by the location of occurrence and change of ore-forming rock mass and its intersection with NE trending fault structure.In the study area,hydrothermal alterations are developed,such as dolomitization,silicification,potassification,chloritization,sericitization,carbonation and kaolinization,among which silicification and dolomitization are the geological indicators for tungsten and molybdenum prospecting,and silicification and sericitization are the geological indicators for silver polymetallic prospecting.The Bouguer gravity anomaly in the area is negative,and the area with a large negative value is the mineralized area;the positive and negative magnetic field gradient belt and the corresponding fault structure control the mineralized area and distribution,which forms the geophysical indicators for prospecting.The anomalies of Au,Ag,Mo,W,Sb and other elements in regional geochemical exploration,the anomalies of W,Mo,Au,Ag,Sb and other elements in large-scale soil survey(1:20000),and the anomalies of single element are well matched.And the obvious assemblage anomaly in the concentration center is the geological indicator for ore prospecting.According to the favorable degree of ore-forming geological conditions and the development degree of prospecting indicators,combined with the known characteristics of mineralization development,the prospecting potential of the study area is evaluated,two metallogenic prediction areas are delineated,and three prospecting target areas are optimized,providing the selection and scientific basis for the subsequent exploration work.