Geochemical Characteristics And Geochronology Study Of The Neo-archean Metamorphic Plutonic Intrusive Of The Toudaoliu Rive Area In The Huadian Of Jilin Province

This paper systematically study the geochronology and geochemistry of Neo-Archean metamorphic plutonic intrusions of the Toudaoliu rive area in City of Huadian of Jilin province, NE China, as well as conducting analysis on the basis of geochemical characteristics were accurate dating. lt focused on the two categories in the study area metamorphic plutonic intrusive rocks of magmatic origin, evolution mechanism and tectonic environment of formation..The Toudaoliu rive area is located in eastern jilin province changbai mountains, in eastern margin of North China Block(NCB), Metamorphic plutonic intrusive rocks is the main intrusive rocks in the study area, mainly for New-Archean TTG rock series and the Paleoproterozoic massive granites. TTG rock series has undergone amphibolite facies metamorphism, late superimposed greenschist facies retrograde metamorphism by tonalite gneiss, granitic gneiss and a few Austrian long granite; variable potassic granite experienced only greenschist facies metamorphism, a small amount of early massive quartz diorite and granodiorite magmatism.According to research results of zircon U-Pb isotopic dating and rock structural characteristics, the deterioration of the region plutons into two magmatic cycle, early cycles of the strongly deformed tonalite rocks- Austrian feldspar granite intrusion and late the granodiorite composition, isotopic age 2551-2515 Ma. Petrological, geochemical characteristics indicate the main source material for the shell source TTG rock series, trace elements and REE geochemical characteristics show that the magma from the lower crust, which formed in the front plate collision island arc or active continental margin environment.Late magmatic cycle by the massive structure of quartz diorite- granodiorite and late intrusive granite block potassium isotope age 2477-2436 Ma. In its massive structure with the early phase difference TTG rock series, marking the tectonic setting of magma output mutated. Variable potassic granite is a high-K calc-alkaline land in the inner shearing Anatexis, TTG molten rock formation- magmatic series shoshonites evolution; quartz diorite- granodiorite magma source group early TTG gneiss zone is similar to the thickened mafic lower crustal rocks. They formed in the late collisional orogenic extension- environmental collapse.In summary, about 25 billion years, occurred in the study area in a major subduction- collision split event, TTG rock series formed in subduction stage, late collision caused high amphibolite facies- regional metamorphism and amphibolite facies deformation, collision orogenic extension late- the collapse of the role of the thickened crust partial melting of the early formation of calc-alkaline quartz diorite to form granite and the late potassium end.