SEDIMENTS AND STRUCTURE OF THE GULF OF ELAT (AQABA) NORTHERN RED-SEA

The Gulf of Elat (Aqaba), about 180 km long and 15-25 km wide, comprises the southern part of the Dead Sea rift. Its floor is up to 1850 m deep, about 4 km below the neighbouring mountains on land. The Gulf occupies a fault-controlled depression, partly filled by sediments. The structure of the Gulf is dominated by en-echelon faults which delimit three elongated basins that strike N20-25°E. Sedimentation in these basins was syn-tectonic. Their fill consists of turbidities and, pelagic deposits. The recorded thicknesses reach 2-3 km, without reaching basement. The fill extends to more than 7 km below adjacent lands when corrected for erosion. In parts of the basins deformation was fast enough relative to sedimentation as to deform the seafloor. Flexures, arches and small folds were formed. In the southern part of the Gulf sharp upright folds, which form prominent hills, may be of diapiric origin. The basins are flanked by marginal blocks, which are much wider on the western side of the Gulf of Elat than on its eastern side, which consists of a very steep slope. The marginal blocks on the west sometimes form topographic terraces. Alluvial fans and submarine cones are conspicuous on the west side of the Gulf, but are virtually absent on the east side. It seems that the present shape of the Gulf was acquired during the last stage of movement on the Dead Sea rift, when left lateral slip of about 40-50 km took place. Tectonism was strongest in the basins and on the faults which flank them, but the marginal blocks are also involved in active tectonism. © 1979.