Structure de la croute terrestre en Algerie d'après les ondes sisiuiques

Abstract

It has been tried to exploit in the best ways all data of<br />the algerian shocks till 1969 using the various documents and publications<br />found in the Seismological Center of Algiers. Various methods used for the<br />near shocks ( &lt; 700 km) first and for the farther events later, show that:<br />&mdash; The velocities are: Pg = 5,55 km/s, Sg = 3,22 km/s, Pn = 7,77 km/s,<br />Sn = 4,32 km/s at least for the smaller distances; these velocities, relatively<br />little, become greater for distances above 800 km, which means certainly<br />a great increase of velocity in the upper mantle.<br />&mdash; There is no significant variations of velocity between the regions<br />of Algiers and S&oacute;tif.<br />&mdash; The algerian shocks are shallow: most of them have a depth less<br />than 15 km.