Submarine sedimentary bedforms in the Loukkos estuary, Morocco

The Loukkos is among the largest river in Morocco. To date, there has been no thorough investigation of the underwater bedforms in the Loukkos. To characterize variability in bedform geometry, and to provide a detailed description of the morphodynamics of dunes in the river channel, images of the sediment-water interface were collected using an Ocean Server Iver2-62 AUV and an Echosounder 320 BP. Grab samples were taken for understanding sedimentological distribution. Series of bedforms of different sizes are clearly observed in the study area. They are presented as fields developed at depths of 2-10 m. Medium dunes in terms of Ashley's (1990) classification system, are the most dominant. The wavelengths and the heights vary from 1.5 to 52.5 m and 0.3-3.23 m respectively. Overall, the dunes identified along the Oued Loukkos have an asymmetrical cross-section with variable bedforms configuration from 2 D straight crest dunes to sinuous 3D dunes. In addition, the dunes show no clear correlation between dune height and wavelength with depth with previous studies, but this suggest that other parameters should be involved.