Palynological evidence for the latest Oligocene−early Miocene paleoelevation estimate in the Lunpola Basin, central Tibet

Abstract

Uplift of the Tibetan Plateau is ultimately driven by the Cenozoic collision between the Indian and Eurasian plates and their continued convergence. One approach for studying the Tibetan Plateau uplift is to verify the paleoelevation changes from collision to present day. This is important for understanding both the tectonics and the climatic effects. The new high resolution palynological record of the uppermost Oligocene to the lowest Miocene strata from the Lunpola Basin indicates that the vegetation types during the latest Oligocene–earliest Miocene were dominated by mixed coniferous–broadleaved forests being different from the modern steppe vegetation. By using the Coexistence Approach to the fossil pollen records, after calibration the effects of temperature difference and the lapse rate, a maximum paleoelevation of 3190±100m asl was estimated in the Lunpola Basin in the latest Oligocene–earliest Miocene, being 1500 to 2000m lower compared with the previous oxygen isotope paleoelevation in the same region.