The Anti-Atlas Mountains constitute a Late Proterozoic suture zone produced by northward subduction of oceanic lithosphere culminating in the Pan-African orogeny. Southward migration of thrust slices associated with the destruction of the forearc terrane resulted in the uplift and erosion of previously deposited basin sediments. These sediments were subsequently reincorporated into collisional basin deposits of the Tiddiline Formation. The Tiddiline Formation consists of coarsening-upwards sequences of maroon siltstones, sandstones and intraformational conglomerates. These rocks unconformably overlie metamorphosed volcaniclastic rocks of the relict forearc basin and accretionary terrane. Syn- and post-depostional deformation has resulted in folding about gently-plunging fold axes. Folds were subsequently cut by strike-slip faults that strike at a high angle to the basin axis. Deformation of the Tiddiline Formation is attributed to transpressional suturing of the relict forearc terrane to the West African Craton to the south. Collisional basins of the Anti-Atlas Mountains serve as ancient analogs for the destruction of forearc basins in an obliqueconvergent margin setting, such as those of the Western Pacific region.
ASJC Scopus subject areas
- Geochemistry and Petrology