Major, long-lived ENE-WSW lineaments in North Africa and their influence on Proterozoic and Palaeozoic Petroleum systems

Raddadi, M. C.¹, P. Markwick², S. Campbell² (1) GETECH Group, Leeds, United Kingdom (2) GETECH Group,

North Africa is dissected by numerous differently orientated major tectonic lineaments. Some of these are very old affecting the basement and have been reactivated many times during successive orogenic phases. Such lineaments play an important role in controlling the sedimentation in this area as well as the regional and local paleogeography.

The Proterozoic and Palaeozoic tectonic history of North Africa is dominated by long periods of predominantly gentle basin subsidence alternating with short periods of gentle folding and inversion. However, this was interrupted by an important phase of folding, uplift and erosion during the Pan-African orogenic event. Some local rift basins developed episodically, located mainly along the northern African-Arabian plate margin and near the West African Craton / Pan-African Belt Suture. These basins were limited by arches or spurs, mainly along N-S to NE-SW trends.

In a structural, geophysical and sedimentological study of the Algerian Saharan Platform and a previous study in Mauritania, Raddadi (unpublished), we demonstrated the importance of the ~N070 lineaments in controlling the occurrence and distribution of source rocks and reservoirs in this area. These lineaments correspond to Archaean and Palaeo-Proterozoic trends, reactivated during Meso- to Neo-Proterozoic, Palaeozoic and probably Mesozoic times. As such, these play a very important role in the Proterozoic petroleum system of onshore Mauritania (northern margin of Taoudenni Basin) and the Palaeozoic petroleum system in the North African Saharan Platform (Algeria, Libya).