GEODYNAMICAL IMPLICATIONS OF A MOSCOVIAN PALEOMAGNETIC POLE FROM THE STABLE SAHARAN CRATON (ILLIZI BASIN, ALGERIA)

Four different characteristic remanent magnetization (ChRM) orientations have been isolated in the El Adeb Larache formation of the Algerian Sahara (27.45-degrees-N, 8.9-degrees-E). Two of them are interpreted as overprints developed respectively during recent and Permian times. The two others give new Moscovian (28.7-degrees-S, 55.8-degrees-E) and probably Stephano-Autunian (38.5-degrees-S, 57.5-degrees-E) palaeopoles, in good agreement with those previously obtained from the Sahara, but significantly different from the Dwyka "varves" pole (McElhinny and Opdyke, 1968). Comparison with Lower Carboniferous results shows that the latitudinal displacement of Africa during the Carboniferous is mainly related to a clockwise rotation (about 25-degrees) around an axis close to the northeastern border of Africa. Such a motion of Africa agrees well with geological observations and with the Pangea A2 hypothesis.