Fault Pattern, Northwest Corner of Sahara Shield: GEOLOGICAL NOTES

Abstract

The east-northeast-trending fault zone (here termed the Agadir fault) which separates the Sahara shield from the folded mountains to the north, and a north-northeast-trending zone of parallel faults of lesser magnitude extending through Spanish Sahara (Zemmour fault) are interpreted as intersecting geosutures--boundary faults of the crustal block--along which large-scale strike-slip movements took place. The northwest corner of the shield constituted a compressional sector as a result of relative horizontal clockwise displacement along the Agadir and counterclockwise movement along the Zemmour faults, with tensional sectors represented by the regions of the Canary islands and Morocco.