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 Gravimetric data highlight the geometry of the sedimentary infill of the Granada Basin, which constitutes a half-graben tilted to the N-NE. Granada Basin´s high-angle normal faults might be linked at depth to an active low-angle extensional deformation zone. The active Granada Fault zone shows low magnitude seismicity and current average vertical rate that varies from 0.4 to 1.1 mm/yr.

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The main active faults of the Granada Basin are located in its central-eastern sector, where the most important tectonic activity is concentrated, uplifting its eastern part and sinking the western border. Several parameters related to the seismic potentiality of these active, or in some cases probably active, faults in this basin are used for the first time. Many of these faults can generate earthquakes with magnitudes larger than 6.0 M W , although this is not the general case. The fault situated to the N of Sierra Tejeda, probably the one responsible for the big earthquake of 25/12/1884, stands out, because it could generate an earthquake with magnitude 6.9 M W . Although at present all the data needed are not fully known, we consider that the final results show, as a whole, the average expected return periods of the faults in the Granada Basin.

The Granada and Guadix-Baza Basins, the largest Neogene-Quaternary intramontane basins of the Betic Cordillera (southern Spain), undergo active deformation with an associated moderate level of seismic activity. This deformation is controlled by a NNW-SSE compressive regime and an approximate orthogonal tensional regime. The compression produced N70ºE to E-W folds of several scales, the Sierra Nevada antiform being the largest one. The tension is accommodated mainly by NW-SE active normal faults, the most notable being the Baza Fault, in the Guadix-Baza Basin, and the Granada, Sierra Elvira-Dílar and Padul-Dúrcal Faults, in the Granada Basin. In addition, other active faults with different orientations also exist, such as the Alfahuara-Botardo and the Galera faults in the Guadix-Baza Basin, and the Huenes, Obéilar-Pinos Puente and N of Sierra Tejeda Faults in the Granada Basin. Moreover, in several sectors, the presence of orthogonal normal fault sets suggests alternating trends or even radial extension. Slip rates of these active faults, based on geologic markers, vary between 0.06 and 0.5 mm/year. Estimates for the maximum expected magnitude of earthquakes caused by these faults vary between M W 6.0 and 7.0. The N of Sierra Tejeda and the Baza Faults, the larg-ISSN (print): 1698-6180. ISSN (online): 1886-7995