The composite focal solution of a 7-days aftershock sequence to the M 7.2 Azorean earthquake shows a quadrantal repartition of first motions similar to those of all former major earthquakes on this western part of the Azores-Gibraltar line. However for the first time is the choice of the fault-plane constrained, the spatial repartition of aftershocks indicating the slip direction to be N 150 ¿E, with sinistral shear. Interpretations of all former shocks had chosen the conjugate nodal plane as fault-plane, dextral shear along this direction seeming coherent with the difference in average spreading rates North and South of the Azores and approximate direction of the Europe-Africa plate boundary. The direction of rupture documented here coincides with the volcano-tectonic directions dated as recent by F¿raud et al. (1980). This supports a model in which the island volcaNism would be tectonically controlled by the direction of rupture of earthquakes.