MONSOONS VS. WESTERLIES DURING TIBETAN PLATEAU GROWTH AND GREENHOUSE-ICEHOUSE TRANSITION (Invited Presentation)

The ongoing surge of international research on sedimentary basins from the Himalayan-Tibetan orogen and surrounding regions enable to better constrain the geodynamic setting of the India-Asia collision and the associated tectonic growth of the Tibetan Plateau. Consequently, we can now better assess interactions between these forcing mechanisms and Asian paleoenvironmental changes (monsoons, aridification), land-sea distribution, surface processes, paleobiogeographic evolution and the global carbon cycle. We review here some results from the ERC MAGIC project (Monsoons in Asia caused Greenhouse to Icehouse Change?) integrating regional geodynamic constraints, well-dated paleoenvironmental proxy records and climate modelling. MAGIC focuses on the Paleogene period that includes the early collision and plateau growth, associated regional development of monsoons and westerlies over the proto-Paratethys sea and the global Greenhouse to Icehouse cooling. We report well-dated stratigraphic results integrating palynology, stable isotope, provenance and facies analyses from a continuous 51-25 Ma lacustrine record from NE Tibet (Xining Basin) that are compared to Tarim and Tajik Basin records of the proto-Paratethys sea fluctuations and the Pamir tectonic evolution. Together these results allow for a comprehensive paleogeographic and paleoenvironmental reconstructions that are used to constrain initial climate modelling experiments which permit validation of hypotheses on paleoenvironment-climate interactions during this key period.