High-resolution record of geomagnetic excursions in the Matuyama chron constrains the ages of the Feiliang and Lanpo Paleolithic sites in the Nihewan Basin, North China

Abstract

The Nihewan Basin (40°N) in North China is a rich source of Early Pleistocene Paleolithic sites and thus a key area for studying early human evolution in high-latitude (froman early human perspective) East Asia. Here a high-resolution magnetostratigraphic investigation is carried out on a fluvio-lacustrine section in the northeastern Nihewan Basin, which contains the Feiliang and Lanpo Paleolithic sites. Paleomagnetic results suggest that this section records the lower portion of the Brunhes polarity chron and the upper Matuyama polarity chron. Furthermore, the Jaramillo polarity subchron and seven of the nine validated geomagnetic excursions within the Matuyama polarity chron are identified, including the Kamikatsura, Santa Rosa, Intra-Jaramillo, Cobb Mountain, Bjorn, Gardar and Gilsa excursions. The Feiliang artifact layer is located just at the bottom of the CobbMountain excursion, thus its age is estimated to be ~1.2Ma. The Lanpo artifact layer appears to be coeval with the Gilsa excursion, yielding an estimated age of ~1.6 Ma. This study provides new evidence for the presence of early humans in North China before 1.5 Ma and documents the powerful role of geomagnetic excursions: they provide valuable age control points for ongoing efforts to date the early Paleolithic sites.