الفهرس 
AbstractOnly 14 pages are availabe for public view
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Abstract
Coastal soils characterization is a substantial task for understanding the paleo-environmental conditions and engineering implementation. Here, an integrated procedure using remote sensing (RS), direct current resistivity (DCR) and time-domain induced polarization (TDIP) data is applied to characterize the soil on the Nile Delta coast. The proposed protocol was applied in one of a new urban area, as a case study. The study site (New Damietta city) is located along the Nile Delta coast (western of Damietta branch). The digital elevation model (DEM) is generated using relatively old topographic sheets (production dates: 1947-1950) to avoid the impact of the recent human-made topographic artifacts. The defunct streams/buried channels that existed through the Holocene are extracted using a high-resolution DEM. Regarding to multitemporal multispectral RS data, the land use-land cover (LU-LC) is monitored to understand the changes in sediment yield and land degradation over the analysis period. The LU-LC maps indicate that the sabkhat/waterlogged areas were significantly increased while coastal sand and sand dunes dwindled with a rapid rate of new-urban areas development. Applying linear and non-linear geophysical inversion schemes, the heterogeneities within the near-surface coastal soils are characterized by 1D/2D resistivity and 2D-TDIP measurements The inversion results indicate that the dominance of sandy sediments lies along with the streams and sand dunes sites. The high IP response is attributed to clay and/or silt sediments, where the waterlogged areas are dominant. At the same time, the discriminations between the saturated coastal sandy and clayey soils cannot be attained with individual 2D-DCR tomograms. Finally, two Electric Cone Penetration Test (CPTu) with pore pressure measurements indicate that the 2D-TDIP can characterize the clay pockets along the coastal area and discriminate the high conductive layer corresponding to clay from the saltwater intrusion. They provide us with a continuous and detailed stratigraphic profile. Furthermore, some empirical geotechnical parameters were estimated from CPTu data and guide engineers in selective sampling for the critical zone. Accordingly, the present protocol develops coastal soil characterization that leads to providing practical decision support tools to local governments to achieve sustainability for natural resources, health and well-being of these coastal communities.