ESR and ESR/U-series chronology of the Middle Pleistocene site of Tourville-la-Rivière (Normandy, France) -a 1 multi-laboratory approach

Abstract : Tourville-la-Rivière (Normandy, France) is one of the rare Middle Pleistocene palaeoanthropological localities of Northern France. Electron Spin Resonance (ESR) and combined ESR/U-series dating methods were independently applied by different teams on sediments and teeth from this site. The present work provides an overview of this multi-laboratory dating work by integrating a description and discussion of the methodologies employed and results obtained. Results confirm that the ESR/U-series analyses of the teeth are greatly dependent on the U-uptake histories of the dental tissues. Although all teeth come from the same archeological level, the samples analysed by each team display two different patterns for the U-series data. This is most likely related to the different sampling areas selected by each team and may be interpreted as the result of local variations in the geochemical conditions of the surrounding environment. Concerning the ESR dating of optically bleached quartz grains, the use of the multiple centre approach seems crucial when dating such fluvial and fluvio-lacustrine sediments. Our results also confirm the great potential of the Ti-H centre to date late Middle Pleistocene deposits. Despite some (expected) discrepancies related to the independent use of parameters and approaches by the different teams involved in this multi-laboratory study, the whole ESR and ESR/U-series data set collected from Tourville-la-Rivière locality consistently correlates stratigraphic levels D1 to I and associated human occupation to MIS7.