IESDB - the Iberian Evaporite Structure Database

Abstract

Evaporites flow in the solid state under relatively low differential stress and have unique mechanical properties compared to other sedimentary rocks. Worldwide, they control the structural and stratigraphical architecture of many basins and orogens in ancient and active tectonic settings. Moreover, they host mineral deposits and play a key role in petroleum systems because they typically act as seals due to their low permeability, and their ability to flow results in the formation of structural hydrocarbon traps such as folds and faults in their encasing rocks. Additionally, evaporite structures can be used as subsurface storage sites for geo-energy applications and nuclear waste. The systematic characterisation of subsurface evaporite structures is thus key for the development of geoscience-based technologies to address societal challenges. Owing to their value, massive amounts of surface and subsurface information about (among others) the stratigraphy, structure, geochemistry, and petrophysical properties of evaporite structures and their surrounding rocks have been acquired by Earth scientists, petroleum and mining exploration companies, and geological surveys. However, the data often appear segregated (i.e. in the form of database fragments, scientific articles, and unpublished reports), are not systematically organised, and are sometimes not fully accessible. This contribution presents the Iberian Evaporite Structure Database (IESDB), the first comprehensive assessment that focuses on evaporite structures carried out in any region of the world. The IESDB includes information and figures for 150 evaporite structures and their surrounding rocks inventoried in Spain and Portugal and is sourced from other six thematic databases and more than 1500 published and unpublished scientific documents. The database targets undeformed to slightly deformed evaporite successions, outcropping and buried diapirs, evaporite-cored anticlines, evaporite-detached thrusts, and allochthonous evaporite bodies. Collated data include information about the structure, stratigraphy, event chronology, surface and subsurface data availability, mining activity, and key bibliographic references. The IESDB follows the FAIR principles of database management (Findable, Accessible, Interoperable, and Reusable) and is presented as an interactive web page and an open-access database, where indexed structures can easily be selected from a map or browser and filtered by a search engine. The IESDB intends to be a useful resource for teaching (i.e. pointing out examples of exceptional evaporite outcrops), academic and industry research (i.e. identifying knowledge deficits on specific structures or tectonic settings), and for the sustainable exploration and appraisal of mineral resources and geo-energy applications (i.e. representing a terminus a quo for site selection and suitability assessment). The framework provided by the IESDB is an opportunity to enhance the scientific research on Iberian evaporite structures in Spain and Portugal and to take advantage of their scientific and economic potential to tackle important societal challenges faced by these countries. The IESDB is freely available at <a href="https://iesdb.eu" target="_blank" rel="nofollow noopener noreferrer">https://iesdb.eu</a> (last access: 15 June 2023) and the datasets can be downloaded from <a href="https://doi.org/10.20350/digitalCSIC/14586" target="_blank" rel="nofollow noopener noreferrer">https://doi.org/10.20350/digitalCSIC/14586</a> (González-Esvertit et al., 2022).