资源环境科技发展态势分析平台

High topography is the manifestation of the balance between deep and surficial erosional processes. Hence, reconstructions of paleotopography are critical for disentangling records of orogenesis and climate. Here we used a new approach by combining detrital zircon U-Pb geochronology and tetraether-based paleothermometry to characterize the Neogene paleotopography of Northern Tibetan Plateau. Detrital zircon U-Pb data reveal that the Qilian Shan has been uplifted, providing sediments to bounding basins since circa 15.8 Ma. The paleothermometry studies show warm temperatures for paleosols (<12.4-9.5 Ma and 3.7-2.0 Ma) and low temperatures for lacustrine facies (12.4 Ma and 9.5-3.7 Ma). We interpret the different temperatures to reflect the in situ production of tetraethers under warm temperatures within the basin (paleosols) versus terrestrial inputs from high and cold drainage to the paleolake (lacustrine facies). The study supports a topography with significant relief in the Northern Tibetan Plateau since 12.4 Ma.