Since 2013, new excavations have focused on the northern part of the Toca da Janela da Barra do Antonião (TJBA-N) rockshelter, which is located on the edge of the Serra da Capivara National Park in Brazil. Ten sediment samples were dated by multigrain quartz OSL and three samples by feldspar IRSL. Multigrain OSL ages on quartz were assessed using the Central Age Model (CAM) and a Bayesian model built with the R BayLum statistics package. Ages are in good stratigraphic agreement and ages from quartz and feldspars, when available, are internally consistent. Furthermore, we produced a Bayesian model (BayLum) based on OSL ages obtained for the six sediment samples of the main stratigraphy that included stratigraphic constraints and a covariance matrix of errors. Two gaps in sedimentation were detected and can be correlated with climatic changes during the MIS 3 and during the MIS 3 to MIS 2 transition. Finally, our results provide a chronological framework for a new important Pleistocene-Holocene sequence in the region.

This project benefited from French State help managed by the French Research National Agency under the Investissements d'Avenir Program (reference ANR-10-LABX-52). The authors are also grateful to the Nouvelle Aquitaine Region Council (France), the FUMDHAM (Brazil) and the French Ministry of Foreign Affairs for funding. The authors also wish to thank the French National Facility for 14C measurements (LMC14) for performing all 14C activity measurement.

Peer reviewed