Paleoelevation of Tibetan Lunpola basin in the Oligocene-Miocene transition estimated from leaf wax lipid dual isotopes

Carbon and hydrogen isotopic compositions of leaf wax n-alkanes are promising paleoelevation proxies. In this paper, the two proxies were applied to the Dingqing Formation in the Lunpola basin in the central Tibetan Plateau to reconstruct paleoelevation of the basin from the latest Oligocene to the early Miocene. Values of delta C-13 and delta D of C-29 n-alkane were -29.8 +/- 0.7 parts per thousand (n = 38) and -188 +/- 10 parts per thousand (n = 22), respectively. Using the delta C-13 and delta O-18 of the early Miocene Siwalik paleosol carbonate in south Asia as lowland references, paleoelevation of similar to 3000 m was independently estimated from the two isotopic proxies. The results are consistent with recent estimates from pollen and mammal fossil studies. Furthermore, the time-series leaf wax delta C-13 and delta D records consistently suggest a reduction of similar to 900 m from 25.5 Ma to 21.6 Ma, which is likely associated with rapid erosion or tectonic unroofing. (C) 2015 Elsevier B.V. All rights reserved.