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The Quaternary strata in North China primarily consist of fluvial sediments, which react strongly to East Asian Monsoon circulation. However, the records of the Quaternary climate change history in terms of these fluvial sedimentations were limited which impeded understanding the East Asian Monsoon evolution in North China. Thus, a 150 m deep drill core was collected from Changping in the Beijing plain to reconstruct the Quaternary palaeoenvironmental changes. The core was chronologically well constrained using palaeomagnetic and thermoluminescence dating. The magnetostratigraphic result indicated that the Brunhes/Matuyama boundary is at 134.2 m (0.78 Ma) and the age at the bottom of the core is 1.07 Ma. The thermoluminescence (TL) dating of the upper sand at ∼2 m was 10.4 ka. The chemical weathering history since the middle Pleistocene in Beijing plain was reconstructed by using geochemical proxies including selected major element pairs, chemical index of alteration and Al 2 O 3 –CaO*–(Na 2 O + K 2 O) diagrams. The CIA value of the Changping core ranged from 50.3 to 69.4 (average 59.2), which indicated that the sediment has experienced incipient to intermediate chemical weathering during the middle Pleistocene. The result of A–CN–K figure shows a high plagioclase to K-feldspar ratio in the source, which would be indicative of a granodiorite (Gd) source from Jundu Mountains north of the Beijing plain. All the geochemical results revealed a long-term gradual decrease of weathering since the middle Pleistocene, which implied a long-term increasing aridification/cooling in the Beijing plain. [ABSTRACT FROM AUTHOR]

• The late Cretaceous–early Eocene paleoclimate of the Jianghan Basin was studied. • The salinity of the paleolake was mainly controlled by climate change. • The temporal differentiation of the evaporite deposits resulted from tectonics. • The widespread evaporites indicate an extremely arid climate during the Paleocene. • The climate became semi-humid during the early Eocene. The Jianghan Basin, Central China, contains a thick, continuous sequence of early Cenozoic evaporite-bearing deposits that provide a wealth of information about early Cenozoic climate change and evaporites accumulation in East Asia. However, the paleoclimatic history of the basin and its effect on the evaporites are largely unknown. We obtained a deep drill core (SKD1, 2346.5 m long) from the late Cretaceous to early Eocene evaporite-bearing deposits in the Jianghan Basin. Detailed analyses of the lithofacies, mineralogy and geochemistry of the core indicate that salinization and deepening of the lake occurred (corresponding to the Yuyang Formation to the lower Xingouzui Formation), followed by desalting and shallowing (corresponding to the upper Xingouzui Formation). Reconstruction of the spatiotemporal evolution of the evaporites in the Jiangling depression suggests a transition from semi-arid conditions in the late Cretaceous to extremely arid conditions in the initial stage of the Eocene. The climate then became semi-humid during the deposition of the upper Xingouzui Formation, indicating a monsoon or monsoon-like climate in East Asia during the early Eocene. The southward migration of the depocenter of the Jiangling depression, coupled with a warm and extremely arid climate, resulted in the precipitation of evaporites during the accumulation of the upper Shashi Formation and the lower Xingouzui Formation. These results indicate great potential for identifying potash resources within the subsag in the southern Jiangling depression. [ABSTRACT FROM AUTHOR]