This dataset contains X-ray fluorescence (XRF) core scanning data from the Trunvel and Kerallé valleys, Brittany, North-West France. These analyses were carried out as part of the doctoral project Paleogeographic changes and coastal archaeological remains in Brittany during the Middle and Late Holocene: Contributions of a multidisciplinary and multi-scaled approach, with the aim of reconstructing the Holocene evolution of small estuarine systems on the North-West French coast. XRF analyses were carried out using an Avaatech core-scanning system at IFREMER (French Research Institute for Exploitation of the Sea, Plouzané, France) with a 1 cm step along cores TRU-C1 and ANE-C3.