The Geochemical Characteristics And Geological Significance Of Tuogelake Granite Pluton In The East Section Of South Tianshan Orogenic Belt

The South Tianshan orogenic belt is located in the southern central Asian orogenic belt,It is roughly south protuberant arc which is between the Kazakhstan and Tarim plates,It is atypical type of late Paleozoic collision orogenic belt which is formed in the process of thesouth tianshan ocean closing with both sides of the continental collision.By studying thegranite in the South Tianshan orogenic belt,we can reveal the causes of the rock and thecomposition of crustal material,we can also restore the orogenic process and the history oftectonic movement.This paper selected Tuogelake granite pluton in the research area as the research object,which has systematically studied the petrology、geochemistry and Zircon U-Pb chronology，according to the theory of rock formation，The formation age、rock formation、the nature ofthe source area and tectonic environment of Tuogelake granite pluton is discussed.The mainconclusions obtained as follows：The Tuogelake granite pluton is mainly flesh red coarse particles grains moyite graniteand light grey porphyaceous biotite monzonitic granite，the two types of granite is the gradientcontact relationship;The SHRIMP zircon U-Pb datings show that the age of particles grainsmoyite granite is289±4Ma,the age of porphyaceous biotite monzonitic granite is287±3Ma,they are all in the early Permian;The Tuogelake granite pluton belong to high-Kcalc-alkaline,quasi-weakly peraluminous I-typed granite.It is mainly formed by partialmelting of the middle and lower crust material,and accompanied by the interaction ofcrust-mantle magma,the residual material is hornblende and plagioclase;The Tuogelakegranite pluton was produced in collision、Post-collision tectonic setting.Comprehensive analysis, the continental collision of the South Tianshan orogenic beltwas almost over in the early Permian,it enter the stretching stage of Post-collision,TheTuogelake granite pluton formed in the period of the collapse of South Tianshan orogenic beltand continental crust continuously extend thinning.