Morfometría de la red de drenaje, tectónica activa y sismicidad instrumental en el borde occidental de Sierra Nevada (Cordilleras Béticas)

The use of a number o f geomorphic indexes in Sierra Nevada suggests that recentmost and active tectonic activity is concentrated along its SW border. Moreover, a map of the SL-index shows maxima aligned along several bands of NW-SE orientation. Such alignments coincide with high seismicity lineaments, being interpreted as NW-SE oriented active fault zones. NW-SE oriented faults are common in the western border of Sierra Nevada, appearing as very steep highly segmented normal faults. These faults cut across all the tectonic -including M iocene extensional detachments- and lithological boundaries, being responsible for the present-day NE-SW oriented extensional deformation in this region.