Multiphase timing of hominin occupations and the paleoenvironment in Luonan Basin, Central China

Thousands of Paleolithic artifacts have been recovered from Paleolithic sites in the Luonan Basin, in the upper South Luohe River of central China. Their discovery suggests that the basin was an important area for hominin settlement during the Pleistocene. However, the initial timing of this occupation and the environmental conditions for this period are still largely unknown. In addition, the sediments are not well dated and most of the artifacts lie on the surface. In an attempt to resolve these issues, a new systemic paleomagnetic analysis was carried out on the loess deposits that contain in situ stone tools. Our detailed loess–paleosol analyses of the stratigraphy of different sites in the basin and Chinese Loess Plateau shows the accumulation of the loess since at least 1.1 million years (Ma) ago. Moreover, recently discovered in situ cores, flakes and retouched stone tools in these deposits show that hominins used this region repeatedly from 0.8–0.7 Ma to 0.4–0.3 and 0.2–0.1 Ma. Pedostratigraphic analyses, magnetic susceptibility and carbon isotope analyses also indicate that these hominins lived in a subtropical to warm-temperate climate with broad-needle-leaf forest vegetation mixed with grasses.