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The authors comment on a study focusing on the elevation of the India-Asia suture zone during mid-Cenozoic time and the evidence regarding it from Paleosols of Liuqu Conglomerate in China. Topics discussed include the stable isotopes used in the study, the paleoelevation history and geodynamic mechanism of the Himalayan orogen, and the use of plant megafossil leaves and tuffites in Liuqu Conglomerate to analyze geologic history.

We reconstruct the rise of a segment of the southern flank of the Himalaya-Tibet orogen, to the south of the Lhasa terrane, using a paleoaltimeter based on paleoenthalpy encoded in fossil leaves from two new assemblages in southern Tibet (Liuqu and Qiabulin) and four previously known floras from the Himalaya foreland basin. U-Pb dating of zircons constrains the Liuqu flora to the latest Paleocene (ca. 56 Ma) and the Qiabulin flora to the earliest Miocene (21-19 Ma). The proto-Himalaya grew slowly against a high (~4 km) proto-Tibetan Plateau from ~1 km in the late Paleocene to ~2.3 km at the beginning of the Miocene, and achieved at least ~5.5 km by ca. 15 Ma. Contrasting precipitation patterns between the Himalaya-Tibet edifice and the Himalaya foreland basin for the past ~56 m.y. show progressive drying across southern Tibet, seemingly linked to the uplift of the Himalaya orogen. [ABSTRACT FROM AUTHOR]