How the High Atlas belt in Morocco was formed: a new perspective

A paper dealing with the formation of the High Atlas mountain belt in Morocco has been now published in the Journal of Structural Geology. It suggests a new interpretation of the structural evolution of the High Atlas characterized by a long history of transpressional and transtensional reactivations along a major lithospheric shear zone, since the break-up of Pangea. The proposed model highlights how the transpression, characterized by an efficient strain partitioning into belt-parallel and belt-orthogonal components is the main process shaping the High Atlas during the Cenozoic, and may explain the high topographic elevation without crustal thickening, which still remains a controversial topic in the Earth-Science scientific community. The new interpretation is based on geological-structural data integrated with thermochronological and geophysical constraints and is the result of a decades-long collaboration of IGG researchers from Pisa with colleagues from the universities of Milano-Bicocca, Marrakech, and Bonn. Field data were collected during several campaigns mainly carried out within the CNR Short Term Mobility Projects 2009 and 2014 (A. Ellero and G. Ottria) and of the Italy-Morocco bilateral project CNR-CNRST 2016-2017 (scientific leaders: A. Ellero and H. Ouanaimi). The research activities in collaboration with the University of Marrakech will continue thanks to the endorsement of a new bilateral project Italy-Morocco CNR-CNRST for the two-year period 2020-2021 entitled “Fault reactivation study of the long-lived major fault systems of the High Atlas belt (Morocco) (scientific leaders: A. Ellero and H. Ouanaimi). 

Reference: A. Ellero, M. G. Malusà, G. Ottria, H. Ouanaimi, N. Froitzheim (2020). Transpressional structuring of the High Atlas belt, Morocco. Journal of Structural Geology. 135, 104021, doi.org/10.1016/j.jsg.2020.104021.

Paper is available here: https://www.sciencedirect.com/science/article/pii/S0191814119302858

For further information please contact Giuseppe Ottria, CNR-IGG (giuseppe.ottria(at)igg.cnr(dot)it).