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Due to marine recession and stepwise uplift of the Tibetan Plateau during the Cenozoic era, an extremely arid environment and large deserts developed progressively in the interior of Asia. The Tarim Basin is a typical region that experienced this type of palaeoenvironmental evolution. In this study, we apply high resolution palaeomagnetic dating, ESR dating and palaeoenvironmental reconstruction to two parallel sections from an almost 1000 m thick sequence of terrestrial sediments in the central Tarim Basin in order to characterize and date the process of drying and desertification. Our results indicate that the western Tarim Basin started to accumulate terrestrial sediments in a dry land environment at the latest by similar to 4.2 Ma, and that the initial desert was formed by similar to 3.4 Ma from fluvial sands originating from the Tibetan Plateau when the climate became particularly dry in the interior of Asia due to the uplift of the Tibetan Plateau. Variations of the stratum properties, including colour index and magnetic susceptibility, indicate that the aridification trend was significantly intensified at similar to 2.6 Ma, coincident with the onset of the Northern Hemisphere glaciations, and consequently forming the present desert regime. (C) 2010 Elsevier B.V. All rights reserved.