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在南天山褶皱带，分布有大量的花岗岩类岩石。按照由老到新的侵位顺序，岩石类型依次为：闪长岩、似斑状花岗岩、二云母花岗岩和碱长花岗岩。精确的锆石Ｕ－Ｐｂ法研究证明，它们形成于石炭纪末期至早二叠世末期。闪长岩、似斑状花岗岩的岩相学和岩石化学具有Ｉ型花岗岩的特征，而二云母花岗岩充分表现了Ｓ型花岗岩的岩相学和岩石化学特征。与洋中脊花岗岩相比，它们不同程度地富集Ｋ２Ｏ、Ｒｂ、Ｔｈ而贫于Ｔａ、Ｎｂ、Ｚｒ，显示了碰撞造山阶段花岗岩的地球化学特征。碱长花岗岩主要由钾长石、钠长石、石英和富羟铁云母组分的黑云母组成。它们普遍具有高的ＳｉＯ２、Ｎａ２Ｏ＋Ｋ２Ｏ、Ｎｂ、Ｙ、ＲＥＥ（Ｅｕ除外）丰度和Ｆｅ／Ｍｇ比值，以及低的ＣａＯ、ＴｉＯ２、Ｓｒ、Ｂａ、Ｅｕ丰度。从而，系统地显示了Ａ２型花岗岩的普遍特征。证明它们形成于后造山垮塌阶段。各种岩石的εＳｒ（ｔ）界于＋３７．７５和＋２１００．７之间，而εＮｄ（ｔ）界于－４．４２和－６．５１之间，证明它们全部源自于陆壳物质的深熔作用。北天山古洋盆于晚石炭世的闭合导致了南天山碰撞造山作用。而在早二叠世末期，更大范围的大陆伸展作用与南天山的后造山垮塌作用同步。
In the southern Tianshan fold belt, a large number of granite-like rocks are distributed. According to the order from the old to the new emplacement, the rock types are: diorite, plagioclase granodiorite, mica granite and alkali-bearing granite. Precise zircon U-Pb studies have shown that they formed from the end of the Carboniferous to the end of the Early Permian. The petrofacies and petrochemistry of diorite and speckled granite have the characteristics of I-type granites, while the biotite granites fully demonstrate the petrographic and petrochemical characteristics of S-type granites. Compared with the mid-ocean ridge granites, they enriched K2O, Rb and Th to some extent and are poorly depleted in Ta, Nb and Zr, indicating the geochemical characteristics of the granitic rocks during the collision orogeny. Alkaline granites are mainly composed of biotite from potash feldspar, albite, quartz and iron-rich mica. They generally have high abundances of SiO2, Na2O + K2O, Nb, Y, REE (except Eu) and Fe / Mg ratios, and low abundances of CaO, TiO2, Sr, Ba, Eu. Thus, the general characteristics of A2-type granites are systematically shown. Prove that they formed in the post-orogenic collapse. The εSr (t) for various rocks is between +37.75 and +2100.7 and εNd (t) is between -4.42 and -6.51, proving that all of them originate from the deep Melting effect. The closing of the Northern Tianshan ancient ocean basin in the late Carboniferous led to the collision of the southern Tianshan Mountains. In the late Early Permian, the extension of the continent in a larger scope is synchronized with the post-orogenic collapse of the southern Tianshan Mountains.