A new biologic paleoaltimetry indicating Late Miocene rapid uplift of northern Tibet Plateau

The uplift of the Tibet Plateau (TP) during the Miocene is crucial to understanding the evolution of Asian monsoon regimes and alpine biodiversity. However, the northern Tibet Plateau (NTP) remains poorly investigated. We use pollen records of montane conifers (Tsuga, Podocarpus, Abies, and Picea) as a new paleoaltimetry to construct two parallel midrange paleoelevation sequences in the NTP at 1332 ± 189 m and 433 ± 189 m, respectively, during the Middle Miocene [~15 million years ago (Ma)]. Both midranges increased rapidly to 3685 ± 87 m in the Late Miocene (~11 Ma) in the east, and to 3589 ± 62 m at ~7 Ma in the west. Our estimated rises in the east and west parts of the NTP during 15 to 7 Ma, together with data from other TP regions, indicate that during the Late Miocene the entire plateau may have reached a high elevation close to that of today, with consequent impacts on atmospheric precipitation and alpine biodiversity. Description A path for a high plateau The timing of the uplift of the Qinghai-Tibet plateau influences how we interpret the atmospheric circulation and environment tens of millions of years ago. Miao et al. analyzed pollen records from a new sedimentary record to constrain the elevation of the northern part of the plateau. The authors found that the plateau likely obtained its current or higher elevation in the late Miocene, roughly 10 million years ago. —BG Pollen records from the northern Qinghai-Tibet plateau show uplift to its current height about 10 million years ago.