Panafrican to Hercynian deformations in the Mauritanides and tectonic significance of gravity anomalies

Stratigraphy, structure and mineralisation of the Akjoujt area, Mauritania

“…A second event at around 575-550 Ma was also identified. Roussel et al (1984) recognised two lithostructural associations, the external Panafrican to Ordovician nappes and the early Hercynian internal nappes exemplified by the Akjoujt supracrustal rocks. A northward evolution in the age of tectonic activity of the Mauritanides, from Senegal to Morocco, was proposed by L ecorch e (1983).…”

“…Roussel and L ecorch e (1983) interpreted the Mauritanides as a thin, dense, west-dipping slab located along a major crustal discontinuity rooted some 15-30 km within the crust. Geophysical evidence for the allochthonous character of the Mauritanides was outlined by Roussel and L ecorch e (1983) and Roussel et al (1984). The regional gravity patterns generated to the east by the interaction of the Taoudeni Basin with its block-faulted basement can be traced for 30-50 km to the west under the Mauritanides.…”