PALEOMAGNETISM OF THE CONTINENTAL SECTOR OF THE CAMEROON VOLCANIC LINE, WEST-AFRICA

Measurement of samples from 154 sites in the continental sector of the Cameroon Volcanic Line yielded six palaeomagnetic poles, at 243.6 deg rees E, 84.6 degrees N, alpha(95) = 6.8 degrees; 224.3 degrees E, 81.2 degrees N, alpha(95) = 8.4 degrees; 176.1 degrees E, 82.0 degrees N, alpha(95) = 8.5 degrees; 164.3 degrees E, 86.4 degrees N, alpha(95) = 3.4 degrees; 169.4 degrees E, 82.6 degrees N, alpha(95) = 4.6 degrees and 174.7 degrees E, 72.8 degrees N, alpha(95) = 9.5 degrees, belongin g to rocks which have been dated by the K-Ar method at 0.4-0.9 Ma, 2.6 Ma, 6.5-11 Ma, 12-17 Ma, 20-24 Ma and 28-31 Ma, respectively. The res ults are in general agreement with other palaeomagnetic poles from Oli gocene to Recent formations in Africa. The first three poles for rocks formed between 0.4 and 11 Ma are not significantly different from the present geographical pole. Together with other African poles for the same period, this suggests that the African continent has moved very l ittle relative to the pole since 11 Ma. The other three poles for rock s dated between 12 and 31 Ma are significantly different from the pres ent geographical pole, showing a 5 degrees polar deviation from the pr esent pole in the Miocene and 13 degrees in the Middle Oligocene.