On March 20, 2006, a moderate-magnitude earthquake of M w 5.2 hit the region of the Babors mountains, a region located two hundred km east of Algiers (capital of Algeria). More precisely, the epicentre occurred 40 km south-east of Béjaïa, the second most important city in the Kabylian region. The earthquake impacted an area with a radius of about 70 km and caused the death of four persons and injured 68. Damage was mainly observed in Lâalam village (district of Kherrata) where some buildings and old houses were affected. Damage was mainly due to a moderate landslide triggered by the earthquake. Rock falls were also observed near the main cliffs. The maximum observed intensity I 0 was estimated to VII (EMS-98 scale). According to the main shock focal mechanism solution and the spatial distribution of aftershocks, the main shock was reliably found to have been generated by an NS sinistral strike-slip fault. The compressive stress axis r 1 , oriented N325, is in agreement with the direction of convergence between Eurasia and Africa.

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this study describes the deformation in zones affected by regional shearing, and its relation with local factors, in particular rock compositions. the tihaliouine and teg Orak plutons were emplaced close to a major shear zone of the tuareg shield. their magmatic to sub-magmatic fabrics were determined by using measurements of anisotropy of magnetic susceptibility; they are similar to those of some other late Panafrican plutons of the tuareg shield. the eastern part of the teg Orak pluton displays a coherent fabric with a subhorizontal lineation oblique to the 4°50 major shear zone located just to the east. this fabric is clearly related to shearing by a dextral strain-slip movement along the shear zone during magma crystallization. the fabric in the western part of the teg Orak pluton and in the tihaliouine massif presents much more scattered principal axes. It was much less affected by shearing along the shear zone. this difference strongly depends on the nature of the host-rocks: Granitic host-rocks around the tihaliouine and the western part of the teg Orak acted as a rigid block, protecting the intrusions from regional deformation, while basic plutonic and metamorphic host-rocks around the eastern part of the teg Orak pluton had a more plastic behavior and transmitted the regional strain to the intrusion.

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