Post-rift vertical movements and horizontal deformations in the eastern margin of the Central Atlantic: Middle Jurassic to Early Cretaceous evolution of Morocco

Post-rift vertical movements and horizontal deformations in the eastern margin of the Central Atlantic: Middle Jurassic to Early Cretaceous evolution of Morocco

Bertotti, G.
Gouiza, M.

Civil Engineering and Geosciences

Geoscience & Engineering

2012-11-01

Wide regions of Morocco, from the Meseta to the High Atlas, have experienced km-scale upward vertical movements during Middle Jurassic to Early Cretaceous times following the appearance of oceanic crust in the Central Atlantic. The area experiencing exhumation was flanked to the W by a domain of continuous subsidence, part of which is named the Essaouira-Agadir basin. Comparison with vertical movement curves predicted by lithospheric thinning models shows that only 50–60 % of the subsidence documented in the Essaouira basin can be explained by post-rift thermal relaxation and that <30–40 % of the observed exhumation can be explained by processes (in)directly related to the evolution of the Central Atlantic rifted margin. Syn-sedimentary structures in Middle Jurassic to Lower Cretaceous formations of the Eassouira-Agadir basin are common and range from m-scale folds and thrusts to km-scale sedimentary wedges. These structures systematically document coeval shortening generally oriented at high angle to the present margin. As a working hypothesis, it is suggested that regional shortening can explain the structural observations and the enigmatic vertical movements.

post-rift uplift
post-rift deformation
passive margin
Morocco
Essaouira bassin

http://resolver.tudelft.nl/uuid:e6abe10f-9fd7-4c79-aaca-fa1e02270d9d

https://doi.org/10.1007/s00531-012-0773-4

Springer-Verlag

1437-3262

http://link.springer.com/article/10.1007/s00531-012-0773-4

International Journal of Earth Sciences, 101(8)2012

Institutional Repository

journal article

(c)2012 Bertotti, G., Gouiza, M. and Springer