The rise and demise of the Paleogene Central Tibetan Valley

Reconstructing the Paleogene topography and climate of central Tibet informs understanding of collisional tectonic mechanisms and their links to climate and biodiversity. Radiometric dates of volcanic/sedimentary rocks and paleotemperatures based on clumped isotopes within ancient soil carbonate nodules from the Lunpola Basin, part of an east-west trending band of basins in central Tibet and now at 4.7 km, suggest that the basin rose from <2.0 km at 50 to 38 million years (Ma) to >4.0 km by 29 Ma. The height change is quantified using the rates at which wet-bulb temperatures (T-w) decline at land surfaces as those surface rise. In this case, T-w fell from similar to 8 degrees C at similar to 38 Ma to similar to 1 degrees C at 29 Ma, suggesting at least similar to 2.0 km of surface uplift in similar to 10 Ma under warm Eocene to Oligocene conditions. These results confirm that a Paleogene Central Tibetan Valley transformed to a plateau before the Neogene.

Automated summary

Studying the Paleogene topography and climate of central Tibet provides insights into collisional tectonic mechanisms and their connection to climate and biodiversity. Evidence suggests that the Lunpola Basin in central Tibet experienced significant surface uplift of at least 2.0 kilometers over the past 38 million years, transforming it into a plateau.