The relation between water-wells productivity and lineaments morphometry: selected zones from Lebanon

Abstract

Several approaches have been applied to groundwater exploration. In some instances positive results occur, but this is not always the case. This led hydrogeologists to look for a credible approach upon which they can rely during preliminary surveys for groundwater exploration. The development of remote sensing tools along with GIS methodologies gave rise to many new approaches. Most significant among these is the mapping of linear features (lineaments), which appear on satellite images. These features mainly reflect fracture traces, faults or lithologic boundaries and, therefore, are considered as major hydrogeologic parameters to be taken into account. The aim of this paper is to define an empirical relationship between lineament morphometric properties and the productivity of water wells. The three major properties of lineaments, i.e. frequency (Lf), density (Ld) and fault-lineaments (Fl), were analysed using Landsat 7 ETM+ images and GIS techniques. The resultant maps were correlated with the location of water wells in 90 sites from different regions of Lebanon. The resulting output showed an obvious relationship between productive wells and their proximity to fault lineaments. The closer the location of water wells to a ault trace the higher the water productivity. However, this hypothesis can be preliminary utilized in surveys for groundwater exploration, notably in a terrain with intensive rock deformation like that in Lebanon.