Testing of a single grain OSL chronology across the Middle to Upper Palaeolithic transition at Les Cottés (France)

Abstract

a b s t r a c tThe timing of the Middle Palaeolithic to Upper Palaeolithic transition in France is important to help understand when, where and how Neanderthals have been replaced by Homo sapiens. Radiocarbon dating has been the dating workhorse in constructing the chronological framework pertinent to these questions. In this study, we are testing whether single grain OSL dating has the accuracy and precision to be useful as a complementary dating method. The site of Les Cott es provides an ideal testing ground because of its stratigraphic integrity and reliable radiocarbon chronology. We applied single grain OSL dating of quartz to 19 samples and multi-aliquot MET-pIRIR dating of potassium-rich feldspar grains to 5 samples to explicitly test assumptions of pre-depositional resetting of the OSL signal and postdepositional exposure to variable beta dose rates. The good agreement between the single grain OSL and the multi-aliquot MET pIRIR ages suggest that the optical signals of both quartz and feldspar grains were reset prior to deposition and that much of the extra scatter observed in the equivalent dose distribution of quartz grains are likely due to the small-scale differences in beta dose delivered to individual grains. Both the quartz OSL and feldspar MET-pIRIR ages show great consistency with the 14 C ages on bone collected from the same units. This gives confidence in the measurement and analytical approaches used to derive both the equivalent dose and dose rate, the numerator and denominator, respectively, of the luminescence age equation. These results suggest that a systematic and detailed single grain OSL dating study can have the accuracy and precision that is necessary to play a powerful role in the dating of the Middle and Upper Palaeolithic transition and other questions of importance in this time range and geographical area.

Timelines for Human Evolution and Dispersals

“…A similar age for the Châtelperronian industry was obtained at another French site, Les Cottés, where a longer sequence of OSL, pIRIR and 14 C ages spans the Middle to Upper Palaeolithic transition (Jacobs et al 2015) (FIGS. 2C and 2D).…”

Contribution of ESR/U-series dating to the chronology of late Middle Palaeolithic sites in the middle Rhône valley, southeastern France

“…The ESR/U-series method can take over radiocarbon for direct dating of fossils, provided that the near-exclusive dependence of age reliability on accuracy of in situ dosimetry due to poor uranium content in some dental tissues is taken into account. Towards the elaboration of a general chronology for the end of the Middle Palaeolithic and the transition towards the Upper Palaeolithic in Western Europe (e.g., Wood et al, 2013;Jacobs et al, 2015), the new dates from this study suggest that Neandertals occupied the Ard eche area between MIS 4 and MIS 3, and even as early as MIS 5 at Abri du Maras (Layer 5bis) and Grotte des Barasses II (Unit 8), reinforcing the idea of a large Neandertal presence during MIS 4 up Table 2 U-series data (U-content and activity ratios) for tooth samples from Grotte du Figuier, Abri du Maras, Grotte des Barasses II, and Abri des Pêcheurs ( a analysis performed using alpha spectrometry; b analysis performed using ICP-QMS). E ¼ enamel, D ¼ dentine, C ¼ cement.…”

Using ZooMS to identify fragmentary bone from the Late Middle/Early Upper Palaeolithic sequence of Les Cottés, France

“…Here, we explore the potential of proteomically identifying morphologically unidentifiable bone fragments encountered at Palaeolithic sites by employing ZooMS (Buckley et al, 2009) at Les Cott es, a stratified well-dated transitional site containing Mousterian (US08), Châtelperronian (US06), Protoaurignacian (US04inf) and Early Aurignacian archaeological units (US04sup and US02; Jacobs et al, 2015;Roussel and Soressi, 2013;Soressi et al, 2010;Talamo et al, 2012). ZooMS is a quick and simple massspectrometric method to identify mammalian bone fragments up to family/genus level by observing mass values for 7 selected collagen peptides (peptide markers A-G).…”