The "Msissi norite" in Morocco (30.93°N, 4.71°W) from where one of the paleomagnetic reference pole for Africa in Devonian times has been derived, has been revisited and dated. Petrological examination shows that the rock is an alkaline gabbro (teschenite). K‐Ar analyses on fresh biotite yield a 136‐139 Ma age, which infirms the supposed Devonian age. The paleomagnetic study displays several distinct magnetic components.

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Carboniferous limestone and sandstone formations from the Moroccan Meseta and Visean gabbros from the Jebilets massif have been investigated. Palaeomagnetic results reveal the occurrence of different magnetic components. These are (i) a Permian component: Dm = 141.5", Zm = -1.7", N = 4 [Virtual Geomagnetic Pole (VGP) = 33"S, 43.9"E], similar to that found in the Anti-Atlas and in other parts of the Hercynian chain, (ii) a Carboniferous component Dm = 116.6", Zm = 25. lo, N = 9 (VGP = 7.4"S, 54.5"E), consistent with other Carboniferous data from Central Sahara and Morocco, and (iii) a component not previously described from Africa and still undated, with a direction Dm = 77.4", Im = 1.5"; this direction and it's opposite polarity counterpart were found only at one site (21 specimens) in the Jebilets, and at two sites (20 specimens) in the Meseta (opposite polarity). It may represent an older magnetization possibly of Lower Carboniferous age which would imply important rotations of Africa during this period.