TephAta – An online data collection of tephra data from the Atacama Desert

Abstract. Tephrostratigraphy and -chronology are powerful tools using volcanic ash (tephra) layers for establishing stratigraphic correlations and/or to obtain chronological information for different kinds of sedimentary archives. To develop tephrostratigraphic frameworks, which ideally document a most complete spatial and temporal record of regional volcanic activity, precise geochemical and chronological characterization of tephra layers is needed. Based on these frameworks, newly discovered tephra layers can be linked to retrieve stratigraphic and chronological information. Tephrostratigraphic frameworks exist or are under construction for various regions. However, for some regions of the world the potential of these methods is not exploited yet, although being influenced by long-term and frequent volcanism and tephra deposition. One of these regions is the Atacama Desert of northern Chile. There geochemical compositions of Pleistocene tephra layers (volcanic glass) were recently systematically investigated for their stratigraphy and chronology within the scope of the Collaborative Research Centre ‘Earth – Evolution at the Dry Limit’ (CRC 1211). These analyses were accompanied by the development of a tephra database called TephAta, which aims at providing a long-term basis for tephrostratigraphic and -chronological data of the Atacama Desert. TephAta allows digital documentation of the full variety of tephra-related datasets within one database and provides search functions to foster and simplify the continuous expansion of the regional framework following the FAIR (findability, accessibility, interoperability, and reusability) data principles. A first data compilation of 106 tephra samples origin from 91 tephra deposits is now available and will be continuously extended spatially and temporally. TephAta does not only provide a stratigraphic and dating tool for paleoenvironmental or mapping studies, but it also helps to explore the integrity of the explosive volcanic history of the region along with the associated volcanic hazard and risk assessment.