Petrology, Geochemistry And Tectonic Implication Of QinglongCun Group In Yanbian Area

The Yanbian area of research district ( Qinglongcun group) is locate in Chinese northeast , namely Jilin saves Middle-East department . On the tectonics , there have been spcial tectonics environment and complex geological evolution history of the earth . Not only is there the ancient North China plate and Siberia plate, also have the modern board pieces of the Pacific Ocean which is diving . This district is lie in the intersectant transform position which the paleo —Asiatic ocean tectonic domain and the circum —Pacific tectonic domain to deliver , at the same time is also in the triangle area that the circum—Pacific plate , Siberia plate and the North China coerced , its geological structure and geological evolution meaning are always paid attention to for many people . Theoretically it is to locate in continent plate and ocean plate intersectant place . In the view of global structure , at the same time , the research district is in Chinese north to orogenic belt ( in the eastern edge of the Middle —Asia orogenic belt ) , whichis the important composition part of the Middle—Asia orogenic belt . From the ithologic series and adjacent lithologic series of each other contact relation we do not be very clear , with the representative of the Qinglongcun group and Hulan group , we can offer important theory foundation to reveal the north edge reason structure evolution of North China plate through determining for their property and times.At the same time the plate put together and collide roblem between the North China plate and Siberia plate have especial importance in the orogenic geological function study and also offer important nformation for northeast Asian geological research . On area, structure is growth and shows different shape. Research district is located in tectonic intersectant place on the direction of the N-E and N-W. Study district have the characteristic of the marginal —West Pacific Ocean orogenics that fold execpt for microplates group , and form the granite with rare whole world the special structure of " sea " —the magmatic landscape. so it has become now the most have dispute,the most complex , the most easy to have one of new theoretical growing point on compound orogenic belt on continent geology to orogenic belt research at present. Qinglongchun Group is a set of lithological combination through the complexing metamorphic and deformational functions of the multistage sections . where it is contained various differently types of metamophic rocks, which includes mainly : the schistose series, the amphibolite series , the gneiss series of rough grained , and marble division . Since Paleozoic , the destruction and the strong deformation of various geological function make its bounderline be not obvious very much , and it has become distribution in differently times " islet " in granite "sea" , the outspread direction is NNW —NW. This district has suffered from the influence of much issue tectonics, which is complex to cause whole to construct. according as metamophic rock of the structure evidence and structure essential factor that the rock records deliver to cut , displacement and superposed relation , we can distinguish three phases to deformations . On the basis of the reactive relation and order when the metamorphic mineral forms , and research and the observation of plenty of slices , this district identified two phases of metamophic rocks series . Early mineral composition is Amp+Pl+Qz +Bi+Gt,metamorphic facies is amphibolitic facies,the mineral composition of late period is Pl+Qz+Act+Chl+Bi , metamorphic facies is greenschist facies, it reflects this set of metamophic rocks being had gone through the course of the retreated metamorphism . On the base of concluding the forefathers working accomplishment , we have resumed the original rock who different layer position growth of the schis t , the gneiss and the amphibolite by means of petrology and the rock chemical and their produce the structure background of the earth through research district section actual measurement and analysis . Combine the metamorphic deformational structure of feature for Qinglongcun group and microscopical structure observation , as well as its peripheral contrast...