MICROEARTHQUAKE SEISMICITY AND FAULT PLANE SOLUTIONS AROUND THE NEKORSTRIKE-SLIP-FAULT, MOROCCO

Three hundred and twenty eight earthquakes recorded in the course of 5 weeks in 1989 in the central Rif of northern Morocco provided no evid ence for activity on the Nekor fault (the principal geological structu re in the region) itself; most of the seismicity is located northwest of the Nekor fault. Most of the 41 fault-plane solutions show mainly s trike-slip motion (left-lateral on N-S striking planes) with P axes tr ending N145-degrees. This deformation is consistent with the N-S trend ing normal faults caused by the E-W Quaternary extension and with the present relative NW-SE convergence between Africa and Europe. The acti ve deformation around the eastern Rif is better represented by a distr ibuted shear zone than by a strike-slip fault.