Managing, visualising, and archiving geochemical datasets for tephra correlation using the IntChron Integration Tool

There is now a wealth of glass-shard geochemical data for volcanic ash (tephra) layers from a wide range of volcanoes and eruptions, providing invaluable datasets for tephrochronology. However, compiling published data to assess tephra correlations leads to unwieldy files and requires careful management to keep records of sources and other associated metadata. Here we show that a project within the IntChron Integration Tool (Ramsey et al., 2019), an open-access and versatile online application, can be used to effectively store and manage tephra information, geochemical data, and relevant metadata, while also providing visualisation and statistical tools.

The visualisation functionality allows sites to be plotted on a variety of base maps, enables the plotting of tephra concentrations through a sequence, and generates biplots of major and trace elements. The statistical tools are similarly invaluable for investigating compositional variability and relationships, and for assessing the probability that datasets correlate. Many of these tools were developed for the RESET database (Ramsey et al., 2015) and have since been updated and incorporated into the IntChron Integration Tool.

Project files use a JavaScript Object Notation (JSON) text-based file structure, meaning the files remain small, even for large datasets, and are human readable. Moreover, these data files can be easily read by other tools, code, and can be readily uploaded to repositories. An IntChron Integration Tool project supports the entire workflow, from sample and data collection through analysis and interpretation, to the generation of publication-ready plots.

Here we present an example project structure, and exhibit the functionality using published data from distal tephra layers in the Lake Suigetsu core, and proximal eruption deposits from large explosive eruptions of volcanoes across Japan. This project contains over 7000 geochemical analyses from eleven journal articles, demonstrating the power of the IntChron Integration Tool to manage, visualise, and archive comprehensive geochemical datasets.

References:

Ramsey, C.B., Blaauw, M., Kearney, R., Staff, R.A., 2019. The Importance of Open Access to Chronological Information: The IntChron Initiative. Radiocarbon 61, 1121–1131. https://doi.org/10.1017/rdc.2019.21

Ramsey, C.B., Housley, R.A., Lane, C.S., Smith, V.C., Pollard, A.M., 2015. The RESET tephra database and associated analytical tools. Quaternary Science Reviews 33–47. https://doi.org/10.1016/j.quascirev.2014.11.008