Systematic search of circular structures using satellite imagery to identify potential new impact structures in Mauritania

Abstract

Mauritania, with its ancient (Archean to Paleoproterozoic) and desertic terrains and gentle relief, has been under-explored in terms of impact structures. To date, two confirmed impact craters, namely Tenoumer and Aouelloul, and four circular structures for which an impact origin has been suggested, are known in Mauritania. This work aims at a systematic exploration of circular structures in Mauritania and provide a comprehensive database to support their exploration and elucidate their origin. This approach includes multi-scale search on Google Earth images, and a preliminary assessment of their origin using available geological, geophysical, and geochemical data as well as Digital Elevation Models. A total of 50 new circular structures were detected during our survey, adding to four candidates previously identified. They are distributed throughout the territory with an important fraction of them being located in the Taoudeni basin. The diameters of these structures vary from 60 m to 7.5 km with a right-skewed distribution. A preliminary assessment of the possible origins of these circular structures is proposed and the most promising candidates for potential meteoritic impact sites are listed for future investigations.