الفهرس 
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Abstract
Because of the considerable needs of sustainable development and constructing new settlements in the remote areas, geoenvironmental and geotechnical assessment are performed using surface geological and shallow subsurface geophysical methods in Darb el Arbein area, southern Egypt. There are integrated for the surface terrestrial features analysis including; topographical analysis, extracting surface structural lineaments, as well as the hydrological systems characterization; the geoenvironmental variations detection; and investigating the subsurface layers conditions to define the engineering geological information and the prognosis for geotechnical constructions. Remote sensing and geographic information system (GIS) are used to process, interpret and integrate various data and information for the final geotechnical-geoenvironmental assessment needed for decision makers.
The surface geological method is represented by remote sensing study to the terrestrial features through the topographic analysis via generating Digital Elevation Model (DEM), several 2D vertical profiles and different digital topographic maps exhibiting the slope values and directions. Also to extract the surface structural lineaments from the optical satellite imagery (ETM+) and classifying them, according to their bearings and lengths represented by various rose diagrams. In addition, characterizing the hydrological drainage patterns and their network systems to delineate the groundwater accumulations possibility occurred using the (GIS). The Principle Component Analysis (PCA) and band rationing are performed to differentiate and distinguish between the different lithologic units, depending on selecting the suitable principal components (PCs).
The subsurface shallow geophysical method is represented by geoelectric resistivity measurements and borehole well log data, which are processed and interpreted in the form of a geoelectric model composed of three layers of varying arrangement and thickness. They are surfacial dry sand, arenaceous shale and argillaceous shale. Only, the surfacial dry sand layer is represented on the top of the whole area, with very small thicknesses at some sits, but reaches 11 m. at the other locations. The arenaceous and argillaceous shale are multiplied at some locations, while there are some sits represented only by argillaceous shale only. Thickness and true resistivity maps are generated for the represented layers to delineate their spatial distribution. The surfacial dry sands layer shows the higher resistivity values throughout the study area. The shale content increases toward the southern and southwestern directions, as the resistivity values decrease. Moreover, the clay content increases with depth as represented by the argillaceous shale. Some subsurface faults are revealed from the geoelectric resistivity survey.
In may engineering constructions in Darb el Arbein, the geotechnical recovery in the less competent parts, as the northwestern and southwestern parts of the study area, that characterized by higher anisotropy, can be achieved through the pillars supports by steel bars. However, the number of steel bars in a pillar is proportional to the competence level.
The geoenvironmental assessment includes generating the land cover/use classification and its accuracy assessment, using three different fusion algorithms. This is to determine which algorism is the highest accuracy for land cover/uses, based on the accuracy assessment reports and error matrices. Added, geoenvironmental changes detection involve the change percentages of the objects that have been occurred in two different dates.