Thermochronology constraints on the Cretaceous-Cenozoic thermo-tectonic evolution in the Gaize region, central-western Tibetan Plateau: Implications for the westward extension of the proto-Tibetan Plateau

•The Gaize region has experienced three exhumation events of ∼ 100–70 Ma, ∼50–38 Ma and since early Miocene.•The central Tibetan Plateau has undergone five-stage thermo-tectonic evolution since the late Jurassic.•Late Cretaceous exhumation associated with surface uplift in Gaize region represented the westward extension of proto-Plateau.•Low-relief high-elevation topography of the central Tibetan Plateau has established by the early Oligocene.