The Palaeomagnetism of Triassic and Cretaceous Rocks from Morocco

Stable components of magnetization have been isolated in three formations of Triassic age (the Ait-Aadel dolerites, Issaldain dolerites and Titchka sandstone), and one formation of Cretaceous age (the Infracenomanian sandstone) in Central Morocco. When the new Triassic data are combined with existing African Triassic palaeomagnetic data an elongate distribution of palaeomagnetic poles can be identified for both north-west and south-east Africa which trend in a westerly direction away from the mean Mesozoic position. Possible interpretations of this distribution include Tertiary remagnetization, local tectonic rotation, motion of the African plate, and true polar wander, involving a short-lived westerly excursion of the pole. A similar, but apparently more-complicated distribution of poles is evident for the Cretaceous.