During early tectonic evolution, Western Tianshan orogenic belt which is located between Kazakhstan Plate and Junggar Plate passes complex geologic evolution as follows: ①the first event (D1) is recognized from the evolution of Pre-Sinian basement; ②the D2 event is mainly the stable continental crust development of Sinian to Early Ordovician; ③the D3 structures and fabrics are plate divergence-fitting of the Middle Ordovician to the end of Carboniferous; ④the D4 event reveals intercontinental overlaying orogeny of Permian; ⑤the final stage of event (D5) largely indicates the basin-range coupling stage of Mesozoic-Cenozoic. The D3 event can be divided into four secondary stages of tectonic evolution, i. e., the D31 stage in the formation of the South Tianshan oceanic basin of the Middle Ordovician to late Silurian,the D32 stage in the subduction-orogeny of the late Silurian to late Devonian, the D33 stage in the intercontinental collision-orogeny of the late Silurian to early Carboniferous, and the D34 stage in the postcollision of the early Carboniferous to late Carboniferous. Western Tianshan orogenic belt becomes a magnificent compound orogenic belt in the central Asia which passes subduction-orogeny, interacontinental collision-orogeny, interacontinental overlaying-orogeny, interacontinental orogenic cycle and so on, Since Meso-Neoproterozoic.%西天山位于哈萨克斯坦-准噶尔板块与塔里木-华北板块两大板块之间,在漫长的构造演化过程中历经前震旦纪基底形成演化阶段(D1),震旦纪至早奥陶世稳定陆壳发展阶段(D2)、中奥陶世至石炭纪末板块裂解与再拼合阶段(D3)、二叠纪陆陆叠覆造山阶段(D4 )和中新生代盆山耦合阶段(D5)等5个大的发展阶段,其古生代时期中奥陶世至石炭纪末板块裂解与再拼合阶段(D3)又可细化为4个次级演化阶段:中奥陶世至晚志留世早古南天山洋盆形成阶段(D3(1))、晚志留世至晚泥盆世俯冲造山阶段(D3(2))、晚泥盆世至早石炭世初陆陆碰撞造山阶段(D3(3))和早石炭世至晚石炭世后碰撞阶段(D3(4)).西天山造山带自中新元古代以来历经俯冲造山、陆陆碰撞造山、陆陆叠覆造山和陆内再生造山等多机制多旋回的造山作用,终成为横亘于中亚地区的宏伟的复合型造山带.
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