Materials for the investigation of The Seismicity Of Algeria And Adjacent Regions during the twentieth century

Abstract

Dr. Benouar presents a full and integrated study of the recent seismicity of Algeria and adjacent regions during the twentieth century. He has amassed an impressive amount of macroseismic information pertaining to individual earthquakes, which he combines with instrumental information to reassess the origin parameters of each event. In any compilation of earthquakes it is the additional information beyond the bare accumulation of figures and facts that adds interest and social understanding to the scientific appreciation of the earthquakes themselves. For this it is necessary to know the local conditions, and Dr. Benouar brings out for us very vivid1y the differences between reporting procedures at different times this century, and the ensuing difficulties. It would be most difficult for an outsider to gather the information he presents, and he makes good use of his knowledge of his native land, as well as his professional training as an engineer. We thus learn of the reluctance of the colonial powers to report on damage or casualties outside those inflicted on the expatriate community, and the general difficulties of finding information about earthquakes that occurred during the wars of independence, at a time when effects of even major earthquakes were sometimes minor compared to those of the war itself. He also does not spare us details of political difficulties that arose during periods of reconstruction following recent earthquakes. This work is not restricted, however, to description. He examines the underlying tectonics of the area and deduces estimates of hazard and risk in various parts of the country. He then proceeds to examine the engineering consequences and discuss future needs for building codes and civil protection. Dr. Benouar has produced a work which could well form a model for those wishing to undertake comprelzensive studies of seismicity of other areas, and the measures needed to reduce the effects of catastrophic earthquakes.