The morpho-tectonic evolution of the Tibetan Plateau is controlled by complicated interactions between tectonic uplift and surface erosion. The Gangdese batholith in the southern Lhasa terrane is a key orogenic belt for exploring the complicated morpho-tectonic evolution of the Tibetan Plateau. In this contribution, we apply apatite fission track (AFT) thermochronology to constrain the thermo-tectonic evolution of the central segment of the Gangdese batholith. Twenty-four granitoid samples were collected from both river valleys (e.g., the Yarlung and Xiang Rivers) and from the internal batholith areas located farther from river drainage (and/or local faults) networks. All samples exhibit Miocene AFT ages between ∼19.9 and ∼ 6.1 Ma. Inverse thermal history modeling results reveal that the central Gangdese batholith underwent a two-stage accelerated basement cooling in the Miocene. The first cooling stage took place during the late Oligocene to middle Miocene (∼25–15 Ma), this period of moderate to rapid basement cooling coincides with activity along the Gangdese thrust and Great Counter thrust system, and the Oligocene-Miocene delamination of the Lhasa lithosphere and concomitant asthenosphere upwelling. These tectonic processes acted as first-order control on regional basement uplift, denudation and exhumation. Second, a middle-late Miocene (∼14–5 Ma) rapid cooling is widely recognized in the whole Gangdese batholith. We suggest that this middle-late Miocene cooling is due to exhumation in response to tectonic and surface erosion processes such as N-S normal faults and enhanced river incision induced by the intensification of Asian monsoon. Finally, in combination with published low-temperature thermochronological and paleoaltimetry data, it is deduced that the present-day low-relief landscape of the southern Lhasa terrane resulted from a long-term balance between intense regional tectonic activity and surface erosion.

青藏高原的形态构造演化受构造抬升和地表侵蚀复杂的相互作用控制。拉萨地体南部冈底斯岩基是探索青藏高原复杂形态构造演化的关键造山带。在这项贡献中，我们应用磷灰石裂变径迹 (AFT) 热年代学来约束冈底斯岩基中心段的热构造演化。从两个河谷（例如，雅鲁河和湘江）和远离河流排水（和/或局部断层）网络的内部岩基区域采集了 24 个花岗岩样品。所有样品的中新世 AFT 年龄都在~19.9 到~6.1 Ma 之间。逆热历史模拟结果表明，冈底斯中部岩基在中新世经历了两阶段的基底加速冷却。第一个冷却阶段发生在渐新世晚期至中中新世（~25-15 Ma），这一中度至快速的基底冷却时期与冈底斯逆冲断层和大反冲断系统的活动以及渐新世-中新世的分层相吻合。拉萨岩石圈和伴随的软流圈上升流。这些构造过程对区域基底隆升、剥蚀和折返起到了一级控制作用。其次，中新世中晚期（~14-5 Ma）快速冷却在整个冈底斯岩基中得到广泛认可。我们认为，这种中新世中晚期的冷却是由于响应构造和地表侵蚀过程的折返，例如 NS 正断层和亚洲季风增强引起的河流切入增强。最后，结合已发表的低温热年代学和古高程资料，推断拉萨南部现今的低地势地貌是区域强烈的构造活动与地表侵蚀长期平衡的结果。