Genetic-fluid Inclusion Geochemistry And H-O Isotope Constraints Of The Magongma Antimony Gold Deposit In Duoergongma,Maduo,Qinghai

In this study,the duergongma antimony deposit is located in the middle of the indo-chinese antimony metallogenic belt in north bayan kera.Therefore,the study on the metallogenic model of duergongma antimony gold deposit is carried out in order to understand the metallogenic model of the middle and western part of the indo-chinese antimony metallogenic belt in north bayan kera and to perfect the study on regional metallogenic model. Lignite is the main metal mineral in the antimony gold mining area of duergongma,while quartz and breccia are the gangue minerals.Trace amounts of zircon and epidotite are occasionally found.The natural type of mineralized rock is mainly oxidation.The oxidized minerals are limonite,which is produced in fissures in the shape of net veins and honeycomb.The wall rock alteration mainly includes silicification and limonization,followed by sericitization,kaolinization and carbonation.Through research,the formation process of the deposit is divided into:(1)lean ore fossil English stage,(2)quartz-pyrite stage,(3)quartz-stibnite stage and(4)quartz-carbonate stage. Through the same strata by mining near the sample in the study area of rare earth,trace element analysis,the main tectonic environment is continental island arc,H,O isotope analysis,duo,Gong Ma gold ore-forming fluid mainly for primary magma water,the participation of mineralization have built at the same time the water: study of fluid inclusions testing,duo er Gong Ma mining area of uniform temperature between 150 ? 307 ?,the main distribution between 150 ? 250 ?,for the low temperature in the group.The salinity(wt%Na Cl)is between 0.22 and 13.2,which is generally divided into two groups,the middle salinity group is 5?8,and the low salinity group is 1?3.The metallogenic depth is 12.19?13.28 km,and the average metallogenic depth is 12.54 km. Therefore,the metallogenic model of jegongma antimony gold deposit is as follows: the host strata are early Triassic shichangmahe formation.Late Triassic to early Jurassic balyanlkalla subduction northward of ocean basin,and gradually close orogenic,from east to west in the process to make geothermal heat up to drive the primary magma water along the great migration,extraction of activation of surrounding rock of ore-forming material,in the process of regional uplift are built,the mixed water,eventually forming fluid rich in ore-forming materials.The large-scale thrust and strike-slip faults,ductile-brittle shear zones and their associated secondary fault systems in the orogenic process provide a path and place for the migration and deposition of ore-bearing fluids and the formation of structural alteration rock-type antimony gold deposits in the duergongma area deep in the strata.