Application of sedimentological analysis to correlation of eroded layers under beaches with local and regional Pleistocene stratigraphy: A contribution to geological dating of Palaeolithic sites, northern coast of Brittany, France

A distinctive feature of the Palaeolithic of Western France is that most of the sites are along the present coast line and that the archaeological layers are often partially eroded and contained in very residual Pleistocene silty sediments preserved under the beaches. In the absence of radiometric dating, correlations with local deposits and reference to a regional chronostratigraphic scale allow proposal of a geological age. Where direct radiometric or related dating (i.e. OSL) results exist, sedimentological analysis (i.e. “descriptive” sedimentology) can be used either to confirm the dating or to extend the discussion. This paper is based on examples which have been processed over thirty years but that had never been the subject of an overall methodological presentation.