%0 Journal Article
%9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES
%A Chaabout, S.
%A Aoudjehane, H. C.
%A Reimold, W. U.
%A Baratoux, David
%A Youbi, N.
%T Prospecting for possible impact structures in Morocco
%D 2015
%L fdi:010066067
%G ENG
%J Journal of African Earth Sciences
%@ 1464-343X
%K Impact structure ; Morocco ; Circular structures
%K MAROC
%M ISI:000367410400024
%N Part A
%P 339-352
%R 10.1016/j.jafrearsci.2015.08.002
%U https://www.documentation.ird.fr/hor/fdi:010066067
%> https://www.documentation.ird.fr/intranet/publi/2016/01/010066067.pdf
%V 112
%W Horizon (IRD)
%X The current terrestrial impact crater record includes 188 accepted structures (http://www.passc.net/EarthImpactDatabase and Ferriere et al., 2015). This number continues to increase slowly but quite regularly. The heterogeneous distribution of impact structures is strongly influenced by the knowledge about impact cratering of exploration geologists, who have to be familiar with the possible field evidence for impact structures - and ultimately with the recognition criteria accepted for confirmation of new impact structures. For remote and poorly explored areas, satellite imagery is a powerful tool to identify circular structures that, at all scales, could be considered possible candidates for impact structures. Here, we present the results of a first systematic survey of circular structures over the Moroccan surface area (a total of 710,850 km(2)) using the imagery available through the Google-Earth software. Structures whose origins could not be elucidated from available geological data were then visited to determine their origin (impact or non-impact). Thirteen sites with one or more circular structures were investigated but none of them could be associated with an impact event. Instead, our results illustrate the diversity of geological processes that can produce circular structures, including magmatic and tectonic processes, bioconstruction, and even anthropogenic activity. It also demonstrates that circular structures are very common in surface imagery of the Earth but are generally not associated with impact events. This result questions whether this simple approach for the search of impact structures should be extended to other parts of the world. It also emphasizes that remote sensing imagery should not be used in isolation of other data.
%$ 064