Author(s): RM Teeuw
Now that personal computers (pc's) have become more powerful, potable, and affordable, geoscientists can make full use of developments in computer-aided mapping, particularly Geographical Information Systems (GIS). The IDRISI GIS was used to 1) carry out image processing on satellite images; 2) assess the reliability of the interpreted lineaments; 3) create maps showing individual lineament lengths, areal extent of interconnected lineaments, and targets for groundwater boreholes; and 4) incorporate socio-economic factors, by creating maps that show the proximity of villages to sites considered favourable for boreholes. The exact location of each site for drilling was decided on the basis of geophysical surveys over the areas that had been targeted by the remote sensing and GIS analysis. Most of the remote sensing and GIS work was carried out in Ghana in two weeks, during which the ‘ground truth’ of lineament maps was checked. The total cost of the hardware and software used in this project (16-colour laptop pc, portable colour printer, and IDRISI) was slightly less than US$ 2,600. The relatively low cost and ease of use of this system make it a technology that is readily transferable to developing countries.