Occurrence and impact of characteristic earthquakes in northern Algeria

Earthquakes constitute the natural hazard that is one of the main natural threats to the northern part of Algeria because of its geographical setting at the Eurasia-Africa plate boundary. Several active multi-segment reverse faults have been identified near urban areas that may rupture during characteristic earthquakes and produce earthquakes of magnitudes a parts per thousand yen7.0. Characteristic earthquakes are extreme seismic events characterized by long return periods, which can have great societal impact. Earthquakes in northern Algeria are destructive for two main reasons: firstly, the shallow character of the faults and secondly, the vulnerability of the building stock built essentially prior to the implementation of seismic design codes that take into account the level of the seismic hazard. That is why even moderate earthquakes are disastrous in this area.