Abhatoo - Centre Nationale de Documentation

The results of an initial research carried out in the several coastal aquifers are exposed. The studied areas are situated in the northern most part of Morocco. At the northeast are located the detrital aquifers of Smir and Martil-Alila, and in the northwest is located the detrital aquifer of Charf El Akab. The areas are underlain by detrital sediments of Pliocene to Quaternary age. Generally, groundwater has a high salinity and concentrations moder -ated to high of nitrates. The waters are meanly sodium-chloride type in Smir and Mart i l -Alila aquifers. The waters are sodium-chlorid- and calcium-bicarbonate type in Charf El Akab aquifer. The hydrochemical study of the water of the aquifers shows that the salinity is conditioned by human activities (waste water discharge, irrigation water, salt-water i n t rusion) and lithology (dissolution of evaporitic rocks), and by natural processes. In the Smir area, human activity has produced a series of negative effects on the hydrous equi - librium of lagoon "Merja" (recent construction of the Smir dam, and the installation of a marina in the outlet of the merja as well as the development of tourist facilities around the lagoon ) .