Age and paleoenvironment of Paleolithic stone artifact remains discovered in the Tengger Desert, northern China

In northern China, environmental changes in the transitional zone from the sandy desert to the loess plateau have been regarded as an important issue in the understanding of climate changes and the remains of hominin activities found in this zone provide a solid line of evidence to support the reconstruction of environmental conditions during the late Pleistocene. In 2006, many stone artifacts were collected on the surface in the southeastern Tengger Desert, Northern China. The Tengger lithic assemblage is correlated to the Late Middle to Early Upper Paleolithic stage and with the typical and extensively investigated Shuidonggou site some 140 km north–east of the Tengger localities. In order to evaluate both the age and the environmental conditions prevailing during human occupation despite the lack of associated stratigraphies, we have tried to place the Tengger localities into the Late Pleistocene climatic framework using the available published data provided by Mu Us Desert sand–loess sections and records of Tengger paleolake levels, respectively eastwards and westwards from the newly discovered localities. Additionally, an unpublished sand–loess section was studied by optically stimulated luminescence (OSL) near Zhongwei city, around 170 km to the south. All the data suggests that the optimal time for hominin activity in the Tengger Desert would have been from 42 to 22 ka, during a period of relatively humid conditions when the climate of the area was governed by the strengthened summer East Asian monsoon.