Late Cenozoic geomorphic evolution in the northeastern Tibetan Plateau: Constraints on U-Pb age spectra of detrital zircons in the Wuwei Basin, NW China

Abstract

Basin deposits of the northeastern Tibetan Plateau provide an ideal record for understanding the uplift and the geomorphic evolution in NW China. In this study, we present U-Pb age spectra of detrital zircon from the borehole WW-01 in the Wuwei Basin in the northeastern Tibetan Plateau. The results indicate that: (1) The dominant provenance of the Wuwei Basin was derived from Qilianshan Orogenic Belt (QOB) at 10.34–9.51 Ma, 8.18 Ma, 2.02–0.09 Ma, and the Alxa Block (AB) at 8.69 Ma and 8.14–4.51 Ma. (2) The transitions in the dominant provenance area, at 9.51–8.69 Ma and 8.18–8.14 Ma, were controlled by the closely related to the pre-existing landforms of the basin and its periphery. And the transitions of 8.69–8.18 Ma and 4.51–2.02 Ma were prevailing in the uplift of the northeastern Tibetan Plateau. (3) Provenance analysis, integrated with the sedimentary and structural analysis, show that the initial uplift of the northeastern Tibetan Plateau in the Cenozoic occurred at ca. 8.25 Ma, and the last uplift occurred at ca. 2.58 Ma, corresponding to the geomorphological formation of the northeastern Tibetan Plateau.