An application of hierarchical Bayesian modeling to better constrain the chronologies of Upper Paleolithic archaeological cultures in France between ca. 32,000–21,000 calibrated years before present

Abstract

Investigations of chronology play a key role in the majority of archaeological research endeavors and are particularly pertinent to examinations of culture-environment relationships, especially during periods characterized by rapid and marked climatic variability and environmental reorganization. Rigorous evaluations of available data and robust methods are required if one wishes to reconstruct reliable chronologies, and this is especially the case when examining periods that are associated with a relatively few radiometric measurements. Such is the case for the Upper Paleolithic archaeological record documented in present-day France from 32,000 to 21,000 calibrated years BP. We take into account critically examined radiocarbon measurements from contextually secure archaeological contexts and employ a recently-developed method of Hierarchical Bayesian Modeling to reconstruct the chronology of archaeological cultures from the Middle Gravettian to the Badegoulian. The calculated chronological 2 intervals for each typo-technologically defined culture phase are compared to the Greenland ice core climatic record and a terrestrial paleoenvironmental record from Bergsee Lake (Southern Germany)itself expressed in calendar years calculated with the same calibration curve employed in our age model-thereby permitting each archaeological culture to be correlated accurately with documented paleoclimatic variability. 1.1. Late Pleistocene climatic variability 1 LabEx LaScArBx "IMPACT" (W. Banks, dir.) Programme Collectif de Recherches "SaM" (S. Ducasse and C. Renard, dirs.) Programme Collectif de Recherches "Cassegros" (S. Ducasse and J.-M. Le Tensorer, dirs.) Programme Collectif de Recherches "Casserole" (A. Lenoble and L. Detrain, dirs.

THE ABRI CASSEROLE (DORDOGNE, FRANCE): REASSESSING THE14C CHRONOLOGY OF A KEY UPPER PALEOLITHIC SEQUENCE IN SOUTHWESTERN FRANCE

“…This produced a result (19,300 ± 120 BP: 23.5-22.9 cal ka BP) that correspond well to the age obtained for the burned bone sample from NA7b (19,020 ± 110 BP: 23.2-22.5 cal ka BP), for which the complete pretreatment process was employed. Both results are consistent with reliable regional and extra-regional Upper Solutrean data (Banks et al 2019).…”

“…NA6-NA4: Table 1) is approximately 1000 years older than the previous beta counting ages carried out in the 1990s. Once calibrated, the four stratigraphically wellordered measurements fall within the 23.3-21.1 cal ka BP interval (NA6: 19,110 ± 70 BP: 23.3-22.7 cal ka BP; NA4: 17,760 ± 100 BP: 21.8-21.1 cal ka BP), thus covering the entire currently accepted Badegoulian AMS chronology (Banks et al 2019). These results serve to restore the chronological coherence of the Badegoulian sequence at Casserole and allow these assemblages to be reliably included in inter-site comparisons.…”

“…This program also benefited from the scientific and financial support of the IMPACT project (W. Banks dir. ) that concerned, in part, the same chronological issues (Banks et al, 2019). Thus, based on the information presented above, along with additional research on the post-Solutrean assemblages, which included inter-layer refitting analyses, this new dating effort had three principal objectives:…”

“…Thus, these data place the Solutrean-to-Badegoulian transition at ca. 23 cal ka BP (Ducasse et al 2014(Ducasse et al , 2019bRenard and Ducasse 2015;Banks et al 2019).…”

“…AMS method, pretreatment process developments, etc.) have served to refine our chronological understanding of the period from the Gravettian to the Magdalenian in southwestern France (Henry-Gambier et al 2013;Ducasse et al 2014;Langlais et al 2015;Barshay-Szmidt et al 2016;Banks et al 2019;Verpoorte et al 2019;Ducasse et al 2019b). The available beta counting ages for the Table 1 The Casserole lithostratigraphic and archaeological sequence (according to Detrain et al 1991;Detrain 1992aDetrain , 1994Aubry et al 1995;Aubry and Almeida 2013 Badegoulian levels now appear to be in conflict with the currently accepted AMS chronology for the end of the Pleniglacial in southwestern Europe.…”