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Unlike radiometric methods based on the measurement of radioactive growth or decay of isotopes (e.g., 14C, 40Ar/39Ar, 230Th/234U), the application of radiation exposure dating methods (OSL, TL, ESR) requires the acquisition of data from the sample itself, in addition to those related with its surrounding environment.Indeed, for Electron Spin Resonance (ESR) dating of tooth enamel, the origin of the sample as well as its sedimentary context must be well known to ensure an accurate dose rate reconstruction.Consequently, we advise that the tooth should be collected with at least 150 g of its embedding sediment. It can be done either by inserting TL or OSL dosimeters, which will record the gamma dose rate for at least several months, and/or using a portable gamma spectrometer, which can provide rapid dose rate measurements (in 10 to 30 min).Both kinds of measurements should be done at a 30 cm horizontal depth within the targeted stratigraphical unit, in order to make sure that only the radioactivity of the sediment is recorded.In contrast, the dose rate is evaluated by measuring the radioactivity in the tooth itself (in all the dental tissues constituting the tooth, i.e.enamel, dentine and, sometimes, cement) and in its surrounding (sediment, rocks, etc.).It is therefore crucial to reconstruct the environment of the tooth to ensure a reliable age calculation, especially when variables such as the dose rate from the sediment represent more than 50 % of the total dose rate (e.g., Richard Hereinafter, we provide some recommendations on the tooth sampling strategy to follow for ESR dating, in order to collect suitable samples and to record important data needed for subsequent analyses and dose rates reconstruction.
If these species are lacking from the faunal assemblage, smaller teeth, from species such as cervid and ovicaprid, can be collected, whereas carnivora teeth are usually not recommended, given their thin enamel layer; – the selected tooth should preferentially be well preserved, as previous studies show a direct correlation between fractures and diagenetic weaknesses in dental tissues and preferential migration of U-series elements (e.g.Consequently, the true cosmic dose rate received by the sample decreases according to the thickness of these deposits.In the case of “young” samples (e.g., from Upper Pleistocene deposits), and/or in a very low radioactive context, the contribution of the cosmic dose rate has proven to be significant: for instance, in the case of a cave, the roof thickness and the proximity of the sample from the cave entrance should be recorded and taken into account for cosmic dose rate estimation.L’enregistrement systématique des données de terrain concernant l’échantillonnage est donc essentiel pour la mise en œuvre de la méthode et l’obtention d’âges fiables.