Late Pleistocene site formation and paleoclimate at Lapa do Picareiro, Portugal

• Published in: Geoarchaeology
• Main Authors: Benedetti, Michael M., Haws, Jonathan A., Bicho, Nuno F., Friedl, Lukas, Ellwood, Brooks B.
• Format: Text
• Language: unknown
• Published: LSU Scholarly Repository 2019
• Subjects: caves; Iberia; paleoclimate; Paleolithic; site formation; Greenland; Lapa
• Online Access: https://repository.lsu.edu/geo_pubs/747; https://doi.org/10.1002/gea.21735; https://repository.lsu.edu/context/geo_pubs/article/1746/viewcontent/747.pdf

© 2019 Wiley Periodicals, Inc. The cave site of Lapa do Picareiro, Portugal contains a deep (~10 m) sedimentary sequence representing much of the Middle and Upper Paleolithic, with abundant animal bones, lithic/bone/shell artifacts, and charcoal/ash in hearths. A deposition model based on 49 radiocarbon ages demonstrates average sedimentation rates of 0.1–0.3 mm a −1 between 9 and 45 ka. Extrapolation suggests an age at the base of the excavation of 65–78 ka. The cave sediments are primarily limestone éboulis derived from roof spalling, and muddy fine sediment derived from weathered soil infiltrating through bedrock joints and crevices. Bone preservation in the cave is good and disturbance by bioturbation, dissolution, or erosional processes appears to be limited. Most sedimentological parameters vary conservatively with depth, indicating stable sediment sources over time. Several parameters show good agreement with paleoclimate records over the radiocarbon-dated section. The cold-arid Heinrich stadials are represented by coarse-clast beds with little fine sediment and magnetic susceptibility minima, and mild Greenland interstadials correspond with muddy beds and sharp peaks in magnetic susceptibility. This study complements ongoing archaeological excavation at the site and confirms that the sequence has the proper age, resolution, and preservation to inform on Late Pleistocene cultural and climatic transitions.