ETUDE GRANULOMETRIQUE ET MINERALOGIQUE DES SEDIMENTS SUPERFICIELS DU LITTORAL DE SAÏDIA ET DE L’ESTUAIRE DE LA MOULOUYA (NORD-EST DU MAROC)

Abstract

The study area which is part of the Saïdia littoral consists of two parts: a fluvial portion between the bypass bridge and the mouth of the Moulouya river over a length of 5 km and littoral part between the Saïdia Marina port and the port of marine fisheries of Cap de l’Eau. Sea (L1 to L25) withdrawals have been made according to the radial oriented perpendicularly to the shore line. The average distance between two radial is of approximately 1,2 Km and between two successive samples is about 800 m. sampling in the river ( F1 to F5) were made in the minor bed of Oued Moulouya with 550 metres spacing. Following this oceanographic campaign, the sedimentological characterization of samples is based on granulometric, mineralogical, morphoscopic and calcimetric tests. The granulometric study showed that these sediments consist essentially of moderately graded sands. As to the morphoscopy of quartz, revealed the prevailence of the NU type to the west of the estuary of Moulouya river resulting from erosion of the cliffs calcarenitic and the predominance of the EL type, to the east of the estuary indicating an important marine reworking and the effect of the hydrodynamics of the littoral drift to the East of the beach. The mineralogical analysis of sands reveals the abundance of quartz on the rest of minerals such as feldspar, chlorite, mica and fragments of rocks. While the calcimetric analysis shows that all of the studied sediments contain levels which Etude granulométrique et minéralogique des sédiments superficiels du littoral de Saïdia et de l’estuaire de la Moulouya (nord-est du Maroc) 21 are around 40% in carbonate CaCO3 it is of essentially to the predominance of debris from shells in sediments specially at the level of the marine estrain.