Ancient tree pollen offers new record of northeastern Qinghai-Tibet Plateau uplift: study

LANZHOU, Dec. 10 (Xinhua) -- Chinese scientists used ancient tree pollen to reveal when the northeastern Qinghai-Tibet Plateau was uplifted into its current height, providing new clues to the formation of the roof of the world.

The study published on Friday in the journal Science suggested that the region rapidly uplifted to its current elevation nearly ten to eight million years ago.

The plateau's elevation shaped the region's biodiversity and climate. However, unlike its closely-studied southern part, the evolution of the plateau's northeastern reaches has been less examined.

A group led by Miao Yunfa, a researcher from the Northwest Institute of Eco-environment and Resources under the Chinese Academy of Sciences, evaluated a new sedimentary record from the Qaidam Basin in the northeastern Qinghai-Tibet Plateau containing ancient pollen from mountain conifer species that only grow at specific elevational ranges.

They reconstructed two parallel records of landform uplift spanning 16 million years. They found that about 15 million years ago, the eastern and western regions of the northeastern Qinghai-Tibet Plateau were roughly 1,969 and 1,449 meters above sea level, respectively.

Then, through a rapid uplift over the following several million years, the northeastern reaches grew in height by approximately 2,000 meters -- reaching roughly 3,685 meters in the east about 11 million years ago and 3,589 in the west about 7 million years ago, according to the study.

Afterward, those elevations remained largely stable and only rose slightly, according to the study.