摘要
The onset time of Qilianshan uplift in the Late Cenozoic is an important parameter to constrain the Tibetan Plateau continental dynamics and the climate feedback on the mountain uplift. The apatite fission track and (U-Th)/He dating for samples from northern Qilianshan suggest that the onset time of northern Qilianshan uplift is about 9.5 Ma, with a vertical thrust rate of (0.5 ± 0.1) mm /a and a shortening rate of about (1.4 ± 0.2) mm /a since the Late Cenozoic. The onset time of northern Qilianshan uplift presented in this paper is broadly consistent with the time predicted by “convective removal of lithospheric mantle” and “channel flow” models, and the time when the Chinese continent northwestern monsoon enhanced. Therefore, the onset time of Qilianshan uplift support the argument that the Tibetan Plateau outgrowth during about 5-12 Ma. It does not support that southern Qilianshan uplift at 11 Ma and the northern Qilianshan uplift later than 5 Ma prodicted by the “oblique intra-continental subduction” model.