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To assess the heavy metal contamination in the sediments of Makadi Bay (Hurghada, Egypt), surface samples were collected from 32 locations. Six heavy metals (Fe, Mn, Zn, Cu, Pb and Cd) were analysed using atomic absorption spectrophotometry. The order of trace metal concentration in the samples was Mn>Zn>Pb>Cu>Cd. The analytical results were subjected to univariate statistical analyses to evaluate the distribution and abundance of the metals in the area. The degree of pollution of the sediments by these metals was evaluated by calculating enrichment factors and the geoaccumulation, pollution load and soil pollution indices. The results indicated that all marine sediment locations are practically unpolluted by metals. The high metal concentrations of Pb and Cd due to anthropogenic sources (mean 38.76 and 2.43μgg–1 respectively) recorded in most samples are essentially attributable to the anomalous concentrations of Pb and Cd in these samples. Both natural and anthropogenic sources of Pb and Cd contamination around Makadi Bay are possible. Generally, the levels of heavy metals in the study area do not constitute any serious environmental risk, except in the case of Pb and Cd.

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Acoustic bottom classification utilities have been developed in favor of routine investigation of the seabed texture and grain size, as well as type of sediments. Single beam echosounder, seabed classification systems and QTC VIEW series V were used to map out and identify sediment gradients offshore Nile Delta in front of Damietta promontory. The survey area has an asymmetric shape and of very gentle slope parallel to the shore line at Damietta promontory. Ground truth observation analyses were carried out for 24 grab samples using the classification technique. The acoustic survey data were analyzed with the QTC IMPACT software and classified into five acoustic classes namely (silty clay, clayey silt, silt, sandy silt and very fine sand). The fine sediments (clay and silt) cover the front area of Damietta outlet, forming a stream like shape cutting the center of the area of study, which composed mainly of fluvial sediments. While the sandy sediments, appear as small patches to the east and west. The dominant of the small mean size (fine fractions) is corresponding to the fluvial depositions that form the Nile Delta fan of mainly mud sediments. Actually, since the building of Aswan High Dam in 1964, sediment discharge at the Nile promontories has diminished to almost zero, the recent situation of seabed characteristics is related mainly to the effect of the oceanographic circulation regime dominating the study area. ª 2014 National Institute of Oceanography and Fisheries. Hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).