نبذة مختصرة : The Himalayan orogen, with a length of close to 2500 km, is the result of the col-lision of the Indian and Eurasian continents, which initiated 55 My ago. Since the onset of collision, the morphology of the Himalaya/Tibet region has not ceased to evolve, controlled by tectonics and erosion. At its north-western extremity, the Hi-malayan belt shows strongly contrasting relief, with regions of very high relief encir-cling areas characterised by high elevation and low relief. The best example of the latter areas is without doubt the Deosai Plateau. Located at ~4000 m mean eleva-tion on Kohistan/Ladakh Arc terrains, it is surrounded by strongly incised massifs such as the Karakorum and the Nanga Parbat. These two massifs contain 6 of the 14 summits with an altitude higher than 8000 m in the world. This study presents a morphological analysis coupled with a thermochronologi-cal study of the north-west Himalaya, based on two fieldwork campaigns on and around the Deosai Plateau. This multi-method approach allows us to: (1) precise the morphological characteristics of the north-western Himalayan region and (2) highlight the formation and exhumation history of the low-relief, high-elevation ar-eas, which have been little investigated in this context. Morphological analyses on the scale of the entire north-west Himalaya show that several zones of low relief at high elevation exist west of the Karakorum Fault, both north and south of the Indus-Tsangpo Suture Zone. The thermochronologic study allows us to present the first low-temperature thermochronology data (AFT and (U-Th)/He on apatite and zircon) from this part of the Kohistan/Ladakh Arc. Thermal history modelling using these data and their comparison with published data, sug-gest that the low-relief, high-elevation surfaces have formed since 30-40 Ma. Since this time, these surface evolved slowly, due to very low exhumation rates (~200 m.My-1), unlike the surrounding strongly incised massifs characterised by extremely high exhumation rates (several km.My-1 for the ...
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