ESTIMATION OF SEISMIC HAZARD PARAMETERS IN THE NORTHERN PART OF ALGERIA

In this study, the procedure of the earthquake hazard evaluation recen tly developed by KUKO and SELLEVOLL (1992) is used to estimate seismic hazard parameters in the northern part of Algeria. The new method dif fers from the conventional one because it incorporates the uncertainty of earthquake magnitude, and accepts mixed data containing large hist orical events and recent complete catalogue. The importance of the met hod lies in its ability to estimate from incomplete and uncertain data files the parameter b of the Gutenberg-Richter relationship, the annu al activity rate lambda. of event and the maximum possible magnitude m (max). In this method, the earthquake process is considered to be of t he Poisson type with an annual activity rate lambda, and with a doubly truncated exponential distribution of earthquake magnitude with param eter beta. The northern part of Algeria is subdivided into three zones . For each zone? estimation of b-value, the annual activity rate lambd a and the expected maximum magnitude are obtained. The mean return per iod and the probability of non-exceedence of some magnitude during a t ime period T = 50 and 100 years are computed. The results obtained in this study using this methodology, give a prior picture of seismic haz ard in the northern part of Algeria. In some regions (Mitidja and Chel if basins) these results corroborate not only with the observation, bu t also with seismotectonic results.