New fault-plane solutions of Moroccan earthquakes for the 2005-2008 period

We present new fault-plane solutions, based on P wave first motion, of 10 moderate shocks that occurred in Morocco during the period 2005-2008. In the Middle Atlas and adjacent area, the 3 fault-plane solutions correspond either to reverse or to strike-slip faulting with a normal component, in good agreement with the state of stress determined in this area, reflected by NW-SE horizontal pressure axes. In the central and eastern Rif area, the 3 strike-slip and normal solutions (with ENE-WSW T-axes) are in agreement with the local state of stress. Finally, in the western Rif front, which is undergoing increased seismic activity, the 2 fault-plane solutions obtained (reverse faulting) show unusual NE-trending P-axes that support the model of lateral escape of the Central Rif.

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