Miocene paleoclimate evolution of Central Asia reconstructed from lacustrine successions in SE Kazakhstan

点击翻译按钮获取中文摘要

Continental settings of Central Asia witnessed increased desertification and the establishment of a monsoonal climate during the Cenozoic. These continental-scale climate shifts are connected to the uplift of mountain ranges such as the Tibetan plateau, the final retreat of the Paratethys and the expansion of the South China Sea. The timing of this climatic change relative to global climate evolution and the interplay between regional and global factors in this process are yet poorly understood. This project aims at reconstructing Middle Miocene climate dynamics in Central Asia from orbital to tectonic time scales based on exceptional exposures of lacustrine successions in SE-Kazakhstan. As a first deliverable, we will establish orbital and magnetic stratigraphies for two sections (Aktau Hills and Pyramid Valley) and correlate them to the Geomagnetic Polarity Time Scale. This will provide the age control required for paleoenvironmental and paleoclimatic reconstructions to be carried out as the second main deliverable. In particular, we intend to study the source and timing of increased moisture supply in Central Asia during the Middle Miocene relatively to the uplift of the Tien Shan and sea-level change in the Eastern Paratethys.