Geoelectrical sounding (VES) interpretation in the northwestern lowland of Libya.

A large scale deep vertical electric sounding survey in the north-western sedimentary lowland coast of Libya was carried out. The area is underlain by Cretaceous formations represented mainly by limestone, dolomite with some intercalation of clay and marl. Quaternary sediments (mainly fluvio-eolian and clay deposits) cover the entire area, sebkhas deposits are in the eastern part of this area. The geophysical survey also included drilling wells, some reflection of seismic profiles and field geology. The measurements were carried out to define the lithology, the structure and the general geometry of the water-bearing system in the area and some typical features of the geologic series and existing tectonics in the area were defined. Seismic reflections appeared more significant than electric soundings in delineating various geological formations especially deep ones. Hydrogeologic parameters such as porosity, salt content and thickness of some permeable layers have been determined using well logging data. In the study, a combination of forward, Maquardt inverse and Zohdy automatic algorithm have been utilized in the geoelectric modelling interpretation. Using modified results of the automatic inversion (Zohdy), as first parameters with corresponding geological constraints, would fasten upon the forward and Maquardt inversion (minimising number of iterations).Available from STL Prague, CZ / NTK - National Technical LibrarySIGLECZCzech Republi