中文摘要：

天山是中亚造山带重要组成部分,其中-新生代构造热演化及隆升剥露史研究是认识中亚造山带构造变形过程与机制的关键.本文应用磷灰石（U-Th）/He技术重建中天山南缘科克苏河地区中-新生代构造热演化及隆升剥蚀过程.磷灰石（U-Th）/He数据综合解释及热演化史模拟表明该地区至少存在晚白垩世、早中新世、晚中新世3期快速隆升剥蚀事件,起始时间分别为~90Ma、~13Ma及~5Ma,且这3期隆升剥蚀事件在整个天山地区具有广泛的可对比性.相对于磷灰石裂变径迹,磷灰石（U-Th）/He年龄记录了中天山南缘地质演化史中更新和更近的热信息,即中天山在晚中新世（~5 Ma）快速隆升剥蚀,其剥蚀速率为~0.47mm·a^-1,剥蚀厚度为~2300m.总体上,中天山科克苏地区隆升剥蚀起始时间从天山造山带向昭苏盆地（由南向北）逐渐变老,表明了中天山南缘隆升剥蚀存在不均一性,并发生了多期揭顶剥蚀事件.

英文摘要：

The Tianshan is the main part of the Central Asian Orogenic Belt. Knowledge of Mesozoic-Cenozoic tectonothermal evolution and exhumational history is critical to better understand the deformed process and mechanism of the Central Asian Orogenic Belt. Apatite （U-Th）/He thermochronometry was applied to compile a low temperature, multi-stage thermal history of tectonic uplift and exhumation of the Kekesu section in the South of Center Tianshan. New apatite （U-Th）/He ages and modeling indicated that the Center Tianshan experienced at least three-stage events of uplift and exhumation during Mesozoic and Cenozoic, which initiated at~90 Ma,~13 Ma and~5 Ma, respectively. The three-stage events of uplift and exhumation were also discovered in the South and North Tianshan. Compared with apatite fission track ages, apatite （U-Th）/He ages recorded the younger event （~5 Ma） of uplift and exhumation since the Miocene, which means in the last~5 Ma,~2300 m of overburden was removed during Cenozoic folding and thrusting with a corresponding denudation rate of~0.47 mm·a^-1. It was suggested the initial timing of uplift and exhumation gradually became younger from the South to the North by QTQt modeling of the AHe ages in the Kekesu section during the Mesozoic-Cenozoic, which is more likely that there has been differential uplift/exhumation and multistage unroofing in the South of Center Tianshan.