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文章通过建立花岗岩类类型与地球动力学之间的联系,试图利用分类清楚、测年准确的花岗岩解决本区地壳及造山带演化过程。根据K2O等地壳成熟度的指标,得出了该地区地壳性质由不成熟→半成熟岛弧→成熟陆壳演变;构造环境由不成熟岛弧→成熟的“大陆化”岛弧→大陆碰撞带演化。总结了东天山地区经历了三大地壳演化时期,分别为前寒武纪基底演化阶段陆核及超大陆形成期;古生代古亚洲洋形成演化期和中生代特提斯―印欧板块碰撞阶段板内演化期。反演出了东天山造山带经历了俯冲汇聚及不成熟陆壳形成阶段→弧―陆碰撞及半成熟陆壳形成阶段→碰撞造山及成熟陆壳形成阶段→陆内造山及陆壳改造阶段→中生代板内演化阶段。
By establishing the relationship between granitic types and geodynamics, this paper attempts to solve the evolution of the crust and orogenic belt in this area by using well-defined and accurate dating granites. According to the indicators of crustal maturity such as K2O, it is concluded that the crustal property in this area evolves from immature → semi-mature island arc → mature continental crust; tectonic environment consists of immature island arc → mature “continental” island arc → continent Collision zone evolution. Summed up the East Tianshan area experienced three major crustal evolution period, respectively, the Precambrian basement evolution and continental nucleus formation period; Paleozoic paleo-Asian Ocean formation and evolution and Mesozoic Tethys - Indo-European plate collision plate Evolution period. The inversion shows that the East Tianshan orogenic belt underwent subduction and convergence and immature crustal formation → arc-continent collision and semi-mature continental crust formation → collision orogeny and mature continental crust formation → intra-continental orogen transformation → Mesozoic Plate evolution stage.