Pleistocene sea-level records at Balzi Rossi archaeological area Ventimiglia, Italy.pdf

Presentation at 10th IAG International Conference on Geomorphology, 12-16 September 2022, Coimbra, Portugal.   "One objective of the SPHeritage project is to precisely identify, describe, and geochronologically constrain these palaeo-coastlines. Constraining the sea-level record within the region will assist in understanding how Paleolithic human populations responded to environmental variations related to Pleistocene sea-level fluctuations and help establish the contribution of vertical Earth movements to paleo and predicted sea-level change."</p

Ongoing Multi-method Investigations of Last Interglacial Sea Level

Presented at the "X Young Geomorphologists’ Day, III IAG International Young Geomorphologists’ Meeting & IAG Southern Europe Webinar – Venice 1-2 March 2024"Silas Dean1, Denovan Chauveau1, Ciro Cerrone1, Nikos Georgiou1, D.D.Ryan2, Karla Rubio Sandoval3, Alessio Rovere11Department of Environmental Sciences, Informatics and Statistics, Ca’ Foscari University of Venice, Italy2Department of Earth Sciences, University of Pisa, Italy3MARUM - Center for Marine Environmental Sciences, University of Bremen, Bremen, GermanyKeywords: Sea level change, climate change, last interglacial, MIS 5e, reef modelling, storm eventsThe Last Interglacial (LIG, Marine Isotope Stage 5e, ~125 ka) is a process analogue for a future warmer climate. Thousands of coastal relic landforms and deposits dating back to this period are studied today to obtain insights on pressing questions such as: What was the peak LIG sea level? Was the highstand characterised by single or multiple peaks? Were rapid sea-level changes triggered by sudden ice sheet collapses? The WARMCOASTS project has already compiled a large database of LIG sea-level proxies in the World Atlas of Last Interglacial Shorelines (WALIS), and investigation is also continuing using a number of methods including coral reef stratigraphic forward modelling, storm event and wave modelling, and field surveys for sea-level indicators in South and North America and the Caribbean. The results of this ongoing research may help refine our understanding of ice sheets and sea levels under warmer climate conditionsReferencesChauveau, D., Georgiou, N., Cerrone, C., Dean, S., & Rovere, A. (2024). Sea-level oscillations within the Last Interglacial: insights from coral reef stratigraphic forward modelling. https://doi.org/10.31223/X59T1VGowan, E. J., Rovere, A., Ryan, D. D., Richiano, S., Montes, A., Pappalardo, M., & Aguirre, M. L. (2020). Last interglacial (MIS 5e) sea-level proxies in southeastern South America. Earth System Science Data Discussions, 2020, 1-40.Pastier, A. M., Husson, L., Pedoja, K., Bézos, A., Authemayou, C., Arias‐Ruiz, C., & Cahyarini, S. Y. (2019). Genesis and architecture of sequences of Quaternary coral reef terraces: Insights from numerical models. Geochemistry, Geophysics, Geosystems, 20(8), 4248-4272.Rubio-Sandoval, K., Rovere, A., Cerrone, C., Stocchi, P., Lorscheid, T., Felis, T., ... & Ryan, D. D. (2021). A review of last interglacial sea-level proxies in the western Atlantic and southwestern Caribbean, from Brazil to Honduras. Earth System Science Data, 13(10), 4819-4845.Rovere, A., Ryan, D. D., Vacchi, M., Dutton, A., Simms, A. R., & Murray-Wallace, C. V. (2022). The world atlas of last interglacial shorelines (version 1.0). Earth System Science Data Discussions, 2022, 1-37.</p

<b>Mollusk shells for AAR: Dating the Quaternary shorelines along the coastline of Camarones, Chubut Providence, Argentina</b>

Argentinean Quaternary beach ridges are rich in marine fossil shells. However, the deposits lack material commonly used for the age constraint of coastal deposits, e.g., sediments for luminescence analysis or coral for U/Th analysis. To date, numerical ages have been determined by electron spin resonance and U/Th analysis of shells of the marine mollusk Ameghinomya antiqua, applications for which there are concerns due to the uptake of uranium following organism death. The amino acid racemization (AAR) geochronology method analyzes the extent of protein degradation within shells and provides an estimate of the time elapsed since the cessation of protein formation, commonly equated with the death of the organism. The application of the AAR method to mollusk shells in geochronological studies of Quaternary marine and coastal deposits is well-established, providing relative ages to stratigraphic sequences in the form of D/L values. In this study, we use samples of Ameghinomya antiqua to assess its suitability for AAR analysis in six Pleistocene field sites along the coastline of Camarones’ locality in Chubut Province, Argentina. These field sites represent beach ridges with maximum elevations ranging from ~9 to ~30 m aHT. The D/L values indicate deposits from at least two interglacial periods, consistent with previously published results, i.e., MIS 5 and MIS 11, although some discrepancies are present. The AAR results also show mixed-age deposits, indicating reworking of older deposits into younger ones. Our initial results show that AAR analysis of A. antiqua is able to discern interglacial deposits of differing ages and can be used to assess and complement ESR and U/Th results.Video presented in the EBRAM-CLAMA Congress 2023</p