EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Cenozoic synsedimentary tectonics in the External Rif Zone (Maghrebian Chain, Northern Morocco)

Soufian Maate1, Rachid Hlila2, Ali Maate2, Manuel Martin Martin3, Francesco Guerrera4, Francisco Serrano5, and mario tramontana4
Soufian Maate et al.
  • 1Université Moulay Ismaïl, Laboratoire de Géologie Appliquée, Faculté des Sciences et Techniques, BP. 509, Boutalamine, 52000 Errachidia, Maroc
  • 2Laboratoire de Géologie de l'Environnement et Ressources Naturelles, FS, Abdelmalek Essaâdi University, B.P. 2121, Mhannech II, 93002 Tetouan, Morocco
  • 3Departamento de Ciencias de la Tierra y Medio Ambiente, University of Alicante, AP 99, 03080 Alicante, Spain
  • 4Dipartimento di Scienze Pure e Applicate (DiSPeA), Università degli Studi di Urbino Carlo Bo, Campus Scientifico E. Mattei, 61029 Urbino, Italy
  • 5Departamento de Ecología y Geología, University of Málaga, 28071 Málaga, Spain

The Cenozoic tectono-sedimentary evolution of the External Rif Zone (ERZ) has been studied based on an integrated analysis of twenty-two representative stratigraphic successions grouped in seven sectors from N to S: Tangier, Asilah, Chaouen, Zoumi, Ouezzane, Ourtzarh and the Prerifian Ridges. The ERZ is divided classically, from N to S, into Intrarif, Mesorif and Prerif sub-domains. Each sub-domain is subdivided further in to internal and external. The Cenozoic stratigraphic record of the ERZ can be roughly separated into five main stratigraphic intervals bounded by five main unconformities corresponding to the Cretaceous-Paleogene, Eocene-Oligocene, Oligocene-Miocene, Burdigalian-Langhian and middle-late Mioceneboundaries. Each unconformity can be related to a local or regional tectonic events: (1) the Cretaceous-Paleogene boundary unconformity to the tectonic inversion (from extension to compression) occurring in the alpine Tethys domain in the upper Cretaceous ; (2) the Eocene-Oligocene boundary to a flexure phase in the Atlas front; (3) the unconformity that marks the Oligocene-Miocene boundary can result from the starting of the nappes stacking phase in the Internal Zone; (4) the Burdigalian-Langhian boundary unconformity to the end of structuring of the Internal Zone; and (5) the middle-late Miocene boundary unconformity to the nappes stacking phase in the ERZ. The Paleogene evolution can mainly be correlated with the so-called Eo-alpine orogenic phase, while the Miocene one is related to the Mio-Alpine, both recognized in the western Mediterranean area. As a fundamental part of this research, the analysis of synsedimentary tectonics have been performed, considering tectofacies, unconformity implications and subsidence analysis. Tectofacies (such as, turbidites, slumps, mass flow deposits, synsedimentary folds and faults) are checked from the upper Ypresian succession onward, but more frequently during the Oligocene and Miocene, which point out an upward increase in the tectonic activity. Considering the ERZ as a foreland basin, the Eocene foredeep area would correspond to the Internal Mesorif and Internal Prerif sub-domains. This foredeep was represented by a complex of two “sub-geosynclines” separated by a relative bulge located in the External Mesorif. In this way, the Intrarif could represent the relative orogenic front (advanging on the Internal Rif Zone). The Eocene forebulge was located in the External Prerif, while the Gharb Basin was the backbulge of the system. During the Oligocene the depocentral area migrated southward favoring a homogenization of subsidence in the whole ERZ. In this new configuration, the foredeep would be located in the External Mesorif (formerly a relative bulge) while the External Prerif and the Gharb Basin continued to act as the forebulge and the backbulge of the system, respectively. During the early Miocene a new diversification of depocenter took place with the main foredeep in the Internal Mesorif and secondary foredeeps areas in the externalmost and internalmost Intrarif. In this period, the forebulge should be located in the middle Intrarif. Finally, during middle Miocene foredeep were located in the externalmost Intrarif and Internal Prerif while in the late Miocene depocenter migrates southward to the Extenal Prerif-Gharb areas (formerly forebulge and backbulge areas).

How to cite: Maate, S., Hlila, R., Maate, A., Martin Martin, M., Guerrera, F., Serrano, F., and tramontana, M.: Cenozoic synsedimentary tectonics in the External Rif Zone (Maghrebian Chain, Northern Morocco), EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-2019,, 2023.