Genetic Analysis Of The Antanisoa Graphite Deposit In Madagascar

Madagascar is one of the important producing areas of high-quality coarse flake graphite deposits in the world.With the coarse flake graphite playing a n important role in many new fields,the research on the graphite deposits in Madagascar is becoming more and more important.The genetic study of the deposit is of guiding significance for the exploration of the graphite deposit.However,at present,the level of research on the Madagascar graphite deposits is very low.It is generally believed that the graphite deposits in Madagascar are of metamorphic origin derived from carbonaceous pelitic sediments.In this paper,Antanisoa graphite deposit,which is located 80 km south of Antananarivo,the capital of Madagascar is taken as the research object.Through the study of petrographic?petrochemistry and mineral chemistry characteristics of graphite schist in the mining area,it is found that the view of sedimentary metamorphism is not appropriate.Field geological observation and petrographic study show that there are many phenomena related to fluid filling.Based on previous studies on the geological background o f Madagascar,draw the following recognitions and conclusions:1?According to the study of petrography and mineral chemistry characteristics,it is found that the micas that symbiosis with graphite in the Antanisoa graphite deposit of Madagascar are phlogopite.The formation of these minerals requires the addition of external substances,which provides a basis for the discussion of the genetic of the deposit.2?The tourmaline symbiotic with graphite in the Antanisoa graphite deposit is dravite,which is related to mantle-derived ultramafic rock.3?The view that the Antanisoa graphite deposit in Madagascar is not the cause of sedimentary metamorphism,but is closely related to mantle-derived fluid filling.