Upper Mississippian to lower Pennsylvanian biostratigraphic correlation of the Sahara Platform successions on the northern margin of Gondwana (Morocco, Algeria, Libya)
Pedro Cózar (1) Ian D. Somerville (2) Daniel Vachard (3) Ismael Coronado (4) Alejandra García-Frank (4) Paula Medina-Varea (4) Ismail Said (5) Begoña Del Moral (6) Sergio Rodríguez (1,4)
1- Instituto de Geociencias (CSIC-UCM), c/ José Antonio Novais 12, 28040 Madrid, Spain
2- UCD School of Geological Sciences, University College Dublin, Belfield Dublin 4, Ireland
3- 1 rue des Tilleuls, 59152 Gruson, France
4- Universidad Complutense de Madrid, Dpto. de Paleontología, c/ José Antonio Novais, 12, 28040 Madrid, Spain
5- Division du Patrimoine Géologique (DPG), Direction du Développement Minier (DDM), Ministère de l’Énergie, des Mines, de l’Eau et de l’Environnement, Rue Abou Marouane Essadi BP: Rabat Instituts 6208 – Haut Agdal, Rabat, Morocco
6- Laboratorios Generales del Instituto Geológico y Minero de España, c/ La Calera 1, Tres Cantos, 28760 Madrid, Spain
Abstract – Revision of several important Carboniferous stratigraphic successions in basins in the Saharan Platform allows us to propose distinct biostratigraphical boundaries for the upper Viséan, lower and upper Serpukhovian and lower Bashkirian, with the latter boundary separating upper Mississippian from lower Pennsylvanian strata. The boundaries are not only defined primarily by foraminifers but also incorporate ammonoid and conodont data. This study shows that the positioning of some boundaries differs significantly from previous studies in the region.
For the studied interval, it can be recognized that two well-defined tectonic events were widespread in the entire Sahara Platform: a mostly late Viséan event and a latest Serpukhovian–early Bashkirian event. Both tectonic events show a marked tendency to become younger eastward, and they are compared to the intra-Viséan phase of the Variscan Orogeny and the main phase of this orogeny, respectively.