Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4725460 | Quaternary Geochronology | 2009 | 10 Pages |
Three hominid footprints preserved as casts were found in 1964 in Pleistocene aeolianites of the Nahoon Formation near East London, South Africa. Dating of the footprint-bearing aeolianite proved a lengthy and problematic task. Previous age estimates included a radiocarbon age of 29,090−390+410 years BP [Deacon, H.J., 1966. The dating of the Nahoon footprints. South African Journal of Science 62, 111–113], an infrared stimulated luminescence (IRSL) age of 144 ± 4 ka, a thermoluminescence age of 236 ± 8 ka (TL) and a luminescence subtraction age based on the IRSL and TL estimates of 75 ± 9 ka [Vogel, J.C., Wintle, A.G., Woodborne, S.M., 1999. Luminescence dating of coastal sands: overcoming changes in environmental dose rate. Journal of Archaeological Science 26, 729–733]. Thus there was no consistency among the ages derived using different dating methods. Here we describe optically stimulated luminescence (OSL) dating of quartz grains from a new set of samples collected from the footprint-bearing aeolianite and from associated geological formations. We also re-assessed the dose rate parameters for the sample for which TL and IRSL ages were reported and analysed the OSL signal from this sample. The new OSL dating yielded a coherent series of ages consistent with the stratigraphy as well as global and local sea level history. The indicated footprint age of 124 ± 4 ka thus relates to an important period of modern human evolution.