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南天山是天山山脉的一支,是中亚型造山带的典型代表,它经历了复杂的增生-碰撞过程.关于古南天山洋最终闭合-碰撞造山(碰撞事件)发生的时间一直存在不同的认识,争论由来已久.综合分析南天山造山带的构造、地层、古生物、岩石、地球化学和同位素年代学等方面的资料,特别是对放射虫、蛇绿岩、蓝片岩、火山弧及前陆盆地沉积等地质事实的研究,我们认为,南天山碰撞造山作用起始于二叠纪末-三叠纪初.“,”South Tianshan orogen between Tarim and middle Tianshan has undergone complicate tectonic evolution,especially,the fore-arc accretion during the subduction of the oceanic crust of the ancient south Tianshan ocean under the middle Tianshan volcanic arc.There are various understandings about the beginning time of south Tianshan collision orogeny.Analyzing from the geological data,esp.,radiolarian,ophiolite,blueschist,volcanic arc and foreland basin deposits,The beginning time of collision in south Tianshan is P_3-T_1.