DGPS e paesaggi archeologici: il caso di studio della necropoli di Fehwet (Libia)

The study area corresponds to south-western Fezzan (Libya), a desert area with a few tiny villages and an almost total lack of roads. The first topographical maps of this area that were made available to the public and were used mostly by tourists visiting the country, were the ones made by the Russians on a scale of 1:200000 and 1:500000. These maps, as can be seen, are very difficult to read and are of almost no use for a detailed analysis of the area on a vast scale. Since 1996 our mission has been using Landsat TM satellite images, which are ideal for arge scale territorial survey work. The combined use of these images with pocket GPS has made it possible to effect highly effective survey work, with the development of extremely useful "specific distributive maps" , an example of which is shown here. Of course, in this type of work a certain approximation must be accepted because of the relatively low resolution of the images and the imprecision of the pocket GPS which may be off even 10-20 meters. Up until a few years ago the technology available did not seem to be adequate for intermediate scale surveys; the resolution was too low for the Landsat photos, the pocket GPS were not precise enough, and the use of the Total Station was too complicatedto the point of being prohibitive. Now, the use of the DGPS combined with the high resolution Ikonos images has made it possible to program medium to large scale relief surveys, like the one initiated at the necropolis of Fehwet.