CREDit · Chronological REference Datasets and Sites (CREDit) towards improved accuracy and precision in luminescence-based chronologies

Chronological REference Datasets and Sites (CREDit) towards improved accuracy and precision in luminescence-based chronologies

Generally, our project addressed the challenge of reproducibility of modern science. More specifically, the project's overall aim was to develop and implement new ways to improve the accuracy and precision of luminescence-derived chronologies in Quaternary sciences through reference datasets and samples. Luminescence dating reaches back at least 250,000 years. In geological terms, nothing more than a blink of an eye. However, this period is of uppermost interest for understanding past terrestrial landscape dynamics, from which future landscape evolution crucial to modern societies can be derived. Reliable and reproducible, luminescence-based chronologies are cornerstones to successfully integrating findings from various disciplines in Earth sciences (e.g., geomorphology, soil science, palaeoecology) and archaeology. Furthermore, it allows to match past climate patterns found in terrestrial archives (e.g., loess profiles or varves) and compare them with findings in ice and marine archives. Because of the success and popularity of luminescence dating to establish chronologies, every improvement in accuracy and precision positively impacts numerous studies building on such results. In the mid-and long-term, this situation generates a positive outcome for the society in terms of a better understanding of past landscape dynamics, leading to improved and more precise model predictions for future changes. Furthermore, improved results will automatically lower the costs of such research in the long term by minimising repetitions through better data quality. On a discipline level, towards the broad overall goal of improved accuracy and precision of luminescence-based chronologies, we aimed to create reference data and samples (and tools creating such data), enabling comparisons of methods (e.g., statistical models) and results. We proposed to work with an annually layered sediment core, acting as a reference site and compile those data combined with artificially generated datasets. To that end, CREDit proposed: (1) Sampling and luminescence dating of the core DE3 from the Eifel-Laminated-Sediment-Archive (ELSA), for which a known chronology exists (up to 20 samples), (2) design, test, and distribution of luminescence-based reference datasets, and (3) application of the obtained data, including comparing analysis tools to improve age-depth models. We proposed the statistical programming environment R for designing and testing the reference data. Because of the pandemic, we had reshuffled our work packages and focused more on artificial reference data. With the publication process still ongoing, we were able to sample and analyse the varve core and developed various tools to dynamically generate reference data; a slight modification of the initial plan, where we had proposed static datasets (which are still possible). The developed tools to generate reference data dynamically are novel and will contribute to better luminescence-derived ages. However, to data is not yet clear whether the layer-sediment record can act as the proposed reference dataset because of unexpected (too old) age results.

Data: CORDIS, © European Union