Geochemical Characteristics And Meanings Of Migmatite Rocks In The Datian Area In Panzhihua Sichuan Province

Panzhihua 505 Field II uranium ore belt is controlled by migmatization rocks which are mainly a set of high-grade metamorphic rocks in the migmatization,forming a matrix with biotite plagioclase gneiss,granulite,amphibolite gneiss,migmatite veins in felsic vein;the ore bearing rock is biotite the parent plagioclase and amphibole plagiogneiss and two mica quartz schist;migmatization structure is developed(sodium alkali metasomatism);(1)Panzhihua 505 Field II uranium ore belt by migmatization rocks are mainly a set of high-grade metamorphic rocks in the migmatization,forming a matrix with biotite plagioclase gneiss,granulite,amphibolite gneiss,migmatite veins in felsic veins of ore rock;as the biotite plagioclase and amphibole plagiogneiss and two mica quartz schist;migmatization structure is developed(sodium alkali metasomatism);(2)The geochemical characteristics of mixed rock 505 uranium ore belt of the Panzhihua II field performance for aluminium,calc alkaline series rocks,chemical composition,the content of Si O2 is 51.2%-79.55%,Na K,most of the samples,probably because of sodic alkali metasomatism.The main elements of Fe2O3,Al2O3,Ca O oxide and Mg O decreased with the increase of Si O2,which showed a downward trend,showing consistency and magmatic evolution;trace element spider diagram shows that the trace element spider diagram shows the overall performance for the enrichment of Rb,K,La and other large ion lithophile elements Ba,Ce,Eu,loss and Y,with the characteristics of magma,with the decrease of Be,Sr and Ce,Rb,Rb/Sr,Rb/Ba and linear growth;REE diagram of the overall performance of the right mode of light rare earth enriched the heavy losses,showed obvious negative Eu anomalies.The REE distribution of rock and ore has the same distribution pattern,which indicates that the source of ore-forming material is mainly mixed rock.(3)Based on the data of previous of Kangdian axis mixed rock,combining the dating results,that the formation of the Panzhihua II field 505 uranium ore belt in migmatite Proterozoic to late Proterozoic early before,and the field area migmatization occurred mainly in the late proterozoic.The age of the formation of is 774.7-777.6Ma,which represents the age of uranium mineralization later than the age of the formation of mixed rock and the age of F3 fracture.The F3 fracture was formed after the mixing process,before the intrusion of the vein,and it can be inferred that the formation time of F3 fracture is between 825-840 Ma.(4)The alteration of the surrounding rock of the ? ore belt of the ? uranium deposit in Datian,Panzhihua,is mainly composed of silicification,carbonation,pyrite and hematite(red).With a close relationship with uranium mineralization alteration type in No.1 mine and zoisite chlorite pyrite and chalcopyrite.In ? ore belt KD16 sample is zoisite-obviously epidotization-sericitization,and later hematitization and limonitization.Silicified carbonate alteration: mineralization related to silicification and reddening is generally an obvious type of uranium mineralization.(5)Uranium mineralization is controlled by tectonic and hydrothermal processes.Uranium mineralization and anomalies are distributed along the NE trending tectonic belt,and are commonly found in the outcrops.The sequence of the formation of the metallic minerals is roughly the following: pyrite chalcopyrite;pyrite,zinc manganese ore,zinc manganese ore,iron ore and iron ore.The early stage of uranium bearing rare earth containing ilmenite ilmenite;the late stage of the occurrence of uranyl carbonate;uranyl hydroxide.