Abstract:
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 post-collision 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.