Ali Aydın
Mohamed Salem OUDEIKA
Abstract
Geophysical methods have ultimately proved their efficiency in solving different engineering problems. They permitted the illustration of the subsurface using multidimensional imaging processes by revealing the variations of the physical properties of the subsurface environment. The hydrodynamic events present in the underground have been investigated since the first apparition of the Hydrogeophysics during the 1990s. During the arose of the application of the geophysical methods to reenforce and facilitate the hydrogeological results wealthy literature has grown presenting successful examples in different hydrogeological aspects. The increasing need for groundwater resulting from the growth of population and industrialization better understanding of the hydrogeological problems are of great importance. Industrialization is also presenting a threat not only on the groundwater reserve quantity but also on its quality by the heavy metals liberated to the environment. In this paper, methods as electrical, and electromagnetic methods are presented by illustrating concrete field and laboratory investigations. The results obtained by these methods are reinforced by lithological information collected from mechanical boreholes. Electrical resistivity tomography, and vertical electrical sounding methods have been widely used for the characterisation of the hydrogeological aspect of the subsurface. Electrical resistivity methods relies on measuring the ground Aparent resistivity by injecting an electrical current using exterior electrode and measuring the resulting electrical potential. In order to investigate the shallow layers of a given study area especially for the detection of karstic formation Ground Penetrating Radar is a useful tools having prooved it’s efficiency in such studies. The radargrames are also usefull in red forcing electrical data especially in absence of lithological information. As a quick and non expensive method the magnetic susceptibility methods can be used to detect the contamination degree of the topsoil of vulnerable cachement ares. This method relies on collecting soil samples to be magnetically evaluated in the laboratory, these information are then correlated with geochemical aspect of the study area.
Keywords
Geophysical methods,
Hydrogeophysics,
Industrialization,
electromagnetic methods,
lithological information,
radargrames.
