Abstract
The Bou Azzer ophiolitic complex (Anti-Atlas, southern Morocco) marks the suture of the Pan-African orogenic belt. This fragment of old oceanic crust (697 ± 8 Ma) obducted onto the continental margin of the West African Craton during a collisional event that occurred between 650 and 580 Ma. Very well exposed desert outcrops display serpentinites associated with chromite pods and clinopyroxenolites, ultrabasic and basic cumulates, quartz diorite, a sheeted-dyke complex, basaltic pillow lavas, and red cherts, i.e., the set of lithologies composing an ophiolitic sequence. Other geological units cropping out in the area are: (1) the underlying continental margin of the West African Craton; (2) a volcanic arc next to the oceanic crust represented by the ophiolite; (3) overlying unconformable volcanic and sedimentary rocks. The unusual character of this Neoproterozoic magmatic and tectonic geoheritage site, together with the excellent quality of the outcrops and the relatively easy access to the area, make this complex attractive from both a scientific and a geotouristic perspective. Its declaration as a geoheritage site will serve as a stimulus for the preservation of this singular area.
Similar content being viewed by others
References
Beraaouz EH, Ikenne M, Mortaji A, Madi A, Lahmam M, Gasquet D (2004) Neoproterozoic granitoids associated with the Bou Azzer ophiolitic melange (Anti-Atlas, Morocco): evidence of adakitic magmatism in an arc segment at the NW edge of the West-African craton. J Afr Earth Sci 39:285–293
Bodinier JL, Dupuy C, Dostal J (1984) Geochemistry of Precambrian ophiolites from Bou Azzer, Morocco. Contrib Mineral Petrol 87:43–50
Choubert G, Faure-Muret A (1970) Principales caractéristiques du Précambrien de l’Anti-Atlas. Notes Mém Serv Géol Maroc 229:7–42
D’Lemos RS, Inglis JD, Samson SD (2006) A newly discovered orogenic event in Morocco: Neoproterozoic ages of supposed Eburnean basement of the Bou Azzer inlier, Anti-Atlas Mountains. Precambrian Res 147:65–78
De Kock GS, Gresse PG, De Chevalier LP, Thomas RJ (2000) Notice explicative pour Carte géologique du Maroc au 1/50 000 feuille Taghdout. Notes Mém Serv Géol Maroc 396:1–142
El Hadi H (1988) Etude pétrographique et géochimique des cumulats ultramafiques et mafiques du complexe ophiolitique de Bou Azzer–El Graara. (Anti-Atlas central, Maroc). Thèse 3°Cycle. Université Cadi Ayyad, Marrakech
El Hadi H, Simancas JF, Martínez-Poyatos D, Tahiri A, González-Lodeiro F, Azor A (2008) High-pressure relics and structure of the Bou Azzer Neoproterozoic ophiolite (Anti-Atlas, Morocco). Geogaceta 44:39–41
El Hadi H, Simancas JF, Martínez-Poyatos D, Azor A, Tahiri A, Montenero P, Fanning CM, Bea F, González-Lodeiro F (2010) Structural and geochronological constraints on the evolution of the Bou Azzer Neoproterozoic ophiolite (Anti-Atlas, Morocco). Precambrian Res 182:1–14
Ennih N, Laduron D, Ro G, Errami Z, De Wall H, Boutaleb M (2001) Superposition de la tectonique éburnéenne et panafricaine dans les granitoïdes de la bordure nord du craton ouest africain, boutonnière de Zenaga, Anti-Atlas central, Maroc. J Afr Earth Sci 32(4):677–693
Gasquet D, Levresse G, Cheilletz A, Azizi-Samir MR, Mouttaqi A (2005) Contribution to a geodynamic reconstruction of the Anti-Atlas (Morocco) during Pan-African times with the emphasis on inversion tectonics and metallogenic activity at the Precambrian–Cambrian transition. Precambrian Res 140:157–182
Hefferan K, Karson JA, Saquaque A (1992) Proterozoic collisional basins in a Pan African suture zone, Anti-Atlas Mountains. Morocco Precamb Res 54:295–319
Inglis JD, D’Lemos RS, Samson SD, Admo H (2005) A precise U-Pb zircon age for the Bleida granodiorite, Anti-Atlas, Morocco: implications for the timing of deformation and terrane assembly in the eastern Anti-Atlas. J Geol 113:439–450
Laville E, (1985) Évolution sédimentaire, tectonique et magmatique du bassin Jurassique du Haut-Atlas (Maroc): modèle en relais multiples de décrochements. Thèse d’État. Université de Montpellier, Montpellier
Leblanc M (1975) Ophiolites Précambriennes et gîtes arséniés de cobalt (Bou Azzer, Maroc). Mém–Hors Série. Centre Géologique et Géophysique, Montpellier
Leblanc M (1981) The Late Precambrian Tiddiline tilloid of the Anti-Atlas, Morocco. In: Hambrey MJ, Harland WB (eds) Earth's pre-Pleistocene glacial record. Cambridge University Press, Cambridge, pp 120–122
Leblanc M, Lancelot JR (1980) Interprétation géodynamique du domaine panafricain (Précambrien terminal) de l'Anti-Atlas (Maroc) à partir de données géologiques et géochronologiques. Can J Earth Sci 17:142–155
Michard A (1976) Éléments de géologie marocaine. Notes Mém Serv Géol Maroc 252:1–408
Michard A, Saddiqi O, Chalouan A, de Frizon Lamotte D (2008) Continental evolution: the geology of Morocco. Springer SBM, Berlin Heidelberg
Naidoo DD, Bloomer SH, Saquaque A, Hefferan K (1993) Geochemistry and significance of metavolcanic rocks from the Bou Azzer-El Graara ophiolite (Morocco), Reply. Precambrian Res 62:369–371
Piqué A (1994) Géologie du Maroc: les domaines régionaux et leur évolution structurale. Presses Universitaires du Maroc, Rabat
Saquaque A, Admou H, Karson J, Hefferan K, Reuber I (1989a) Precambrian accretionary tectonics in the Bou Azzer-E1 Graara region, Anti-Atlas, Morocco. Geology 17:1107–1110
Saquaque A, Admou H, Cisse A, Ben Youcef A, Reuber I (1989b) Les intrusions calco-alcalines de Bou Azzer-El Graara (Anti-Atlas, Maroc). Marqueurs de la déformation majeure panafricaine dans un contexte de collision d’arc. C R Acad Sci Paris 308:1279–1283
Soulaimani A, Jaffal M, Maacha L, Kchikach A, Najine A, Saidi A (2006) Modélisation magnétique de la suture ophiolitique de Bou Azzer–El Graara (Anti-Atlas central, Maroc). Implications sur la reconstitution géodynamique panafricaine, C R Geosci 338:153–160
Thomas RJ, Gresse PG, Harmer RE, Eglington BM, Armstrong RA, de Beer CH, Chevallier LC, Martini JE, de Kock GS, Fick T, Macey PH, Ingram BA (2002) Precambrian evolution of the Sirwa window, Anti-Atlas orogen, Morocco. Precambrian Res 137:1–57
Walsh GJ, Aleinikoff JN, Benziane F, Yazidi A, Armstrong TR (2002) U–Pb zircon geochronology of the Palaeoproterozoic Tagragra de Tata inlier and its Neoproterozoic cover, western Anti-Atlas, Morocco. Precambrian Res 117:1–20
Acknowledgments
The research reported in this paper was made possible through financial support by “l’Académie Hassan II des Sciences et Techniques" and the Agencia Espanola de Cooperacion Internacional (AECI), the Inter-Academic Moroccan-Spanish Program projects 17/P/03, 65/04/RE, A/3008/05, A/4938/06 and A/011499/07.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
El Hadi, H., Tahiri, A., Simancas, J.F. et al. Geoheritage in Morocco: The Neoproterozoic Ophiolite of Bou Azzer (Central Anti-Atlas). Geoheritage 3, 89–96 (2011). https://doi.org/10.1007/s12371-011-0032-2
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12371-011-0032-2