The apatite fission track age obtained from the intermediate-acid intrusive rocks on the southern margin of the Gangdise is 37~25Ma. Thermal history modeling process shows that the Gangdise belt has experienced three stages of uplift evolution. The First stage (40~26Ma) was a rapid cooling uplifting stage, which was controlled by the India-Eurasia complete collision, and the Gangdise was raised to the elevation height in 37~26Ma. The second stage (26~8Ma) was an erosion stage, affected by the pedimentation and large thrust system activation, with the existence of alternate erosion and uplift process in this area. The third stage (8~0Ma) was a low cooling stage, during which activation of the NS-striking normal fault systems and rifts led to the formation of basin-mountain system and differential uplifting. In addition, there existed no obvious difference between the north and the south and between the west and the east of Gangdise, with all of these places having similar uplift processes and histories. Thermal history modeling process of apatite fission track age shows that the Gangdise belt has experienced a whole, uniform and phase uplifting.%西藏冈底斯南缘中酸性侵入岩的磷灰石裂变径迹年龄在37~25Ma之间,热史模拟过程反映冈底斯经历了3个阶段的抬升演化.40~26Ma的快速冷却抬升阶段:受控于印度-欧亚大陆完全碰撞拼合的影响,并在37~26Ma抬升至现今海拔高度;26~8Ma的剥蚀阶段:受夷平和大型逆冲推覆活动的影响,出现剥蚀和抬升交替过程;8~0Ma的缓慢冷却阶段:受南北向裂谷作用影响,出现内部差异抬升.此外,北部墨竹工卡地区和南部泽当、桑耶地区,西部桑耶地区和东部泽当地区,均具有相似的抬升过程和历史,没有明显差异,暗示冈底斯经历了整体性、较均一的阶段性抬升过程.
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