Davinia Moreno, geochronologist at CENIEH, is one of the authors of two works to standardize the collection of sediment and fossil teeth so that they can be dated by this method, whose accuracy depends on the quality of the sample.
Three of the most important laboratories in the world in the field of dating by Electronic Spin Resonance (ESR): the Centro Nacional de Investigación sobre Evolución Humana (CENIEN) in Burgos (Spain), the Muséum National d’Histoire Naturelle (MNHN) in Paris (France) and the Australian Research Centre for Human Evolution (ARCHE), in Brisbane (Australia), have come together to standardize the manner of collecting samples of both fossil teeth and sediments for their subsequent dating, and both articles on the latest sampling methodology used at present by geochronologists specialized in ESR have just been published in the journal Quaternaire.
The three laboratories have worked together with the aim of establishing a joint protocol to address fundamental issues such as the most appropriate strategies for each type of deposit, the observations to be made when selecting the best sampling point or how to carry out dosimetry in situ.
Used for the first time over 40 years ago in Japan, ESR is a method that is increasingly more popular among geologists, geomorphologists, and archaeologists, given that it can be used in a wide range of depositional environments and its applicable chronological range covers the entire Quaternary, in other words, the past 2.7 million years.
The sampling strategies used by the different ESR laboratories in recent decades had never been published, and this joint protocol was necessary, taking into account that the accuracy of this dating method depends directly on the quality of the samples collected on site.
However, as stated by Davinia Moreno, geochronologist at CENIEH and co-author of both articles, "this protocol cannot be considered as a sampling guide to substitute the geochronologist, as the years of experience accumulated by specialists are crucial in order to select the most appropriate sampling point".