Prehistoric and historic monumental funerary structures in the “Chott el Jérid” area (Southern Tunisia). The importance of photogrammetry for rapid and complete documentation in Saharan contexts

As part of the Tunisian-Italian archaeological joint mission to the Sahara, a research project (survey and excavation) has focused since 2015 on the study of the funerary archaeology of the prehistoric and historical communities of southern Tunisia. The surveyed area, located along the southern and eastern edges of Chott el Jerid (governorate of Kebili), was selected, after scrutinizing the information collected by the “Service Géographique de l’Armée Française” during the early 20th century about the funerary structures. In this paper, we present two main archaeological funerary contexts and the methodology applied for the photogrammetric documentation of the architectural features of the structures. Then we present the post-processing of the point clouds carried out to obtain a complete data-set for the remote analysis of the excavation sequence of each tumulus. By adopting a multi-scalar approach, from GIS remote analysis to photogrammetric documentation of individual funerary structures, we have tried to optimize the chances of fieldwork activity, taking into consideration whilst so doing the contingencies due to the fluctuating socio-political situation that characterizes some countries of North Africa in recent years

Megalithic Structures of the northern Sahara (Chott el Jérid, Tunisia)

I monumenti megalitici sono una caratteristica archeologica distintiva del pae-saggio sahariano. Partendo da una base piuttosto limitata di lavori editi, e nell’ambito di un programma di ricerca dedicato al Sahara settentrionale, abbiamo avviato nel 2015 un’indagi-ne territoriale sui monumenti in pietra della pre-protostoria e della storia antica della Tunisia meridionale. L’area di studio selezionata è localizzata a est e a sud-est della depressione del Chott el Jérid (governatorato di Kebili). In questo lavoro viene presentata la strategia di ricerca adottata, modulata sulle specifiche caratteristiche locali, quali il pessimo stato di conservazio-ne dei monumenti e la loro incerta cronologia. I nostri risultati, basati sulla combinazione di analisi di telerilevamento, ricognizioni di superficie e scavi di alcuni monumenti, evidenziano una densa occupazione di questa regione del Sahara settentrionale, dove edifici monumentali di possibile funzione funeraria si collocano cronologicamente dalla tarda preistoria fino all’età romana. L’uso persistente dell’area in un arco di tempo molto lungo ne conferma la posizione centrale nelle antiche vie di collegamento transaharianeMegalithic monuments are a distinctive archaeological feature of Saharan land-scape, as indicated by different systematic research projects undertaken so far. Starting from a very low baseline of previous archaeological research, and as part of a comprehensive research programme focussed on northern Sahara, we launched in 2015 a territorial investigation of stone monuments of the pre-protohistory and early history of southern Tunisia. To do this, we selected a sample study area east and south-east of the Chott el Jérid depression (Kebili re-gion) where to conduct field research. In this paper we present the research strategy adopted, planned to address some issues such as the poor state of preservation of the monuments or their uncertain chronology, also known from other parts of the Sahara. Our results, based on the combination of remote sensing analysis, field survey and selected excavations, highlight a dense occupation of this area of northern Sahara, where monumental buildings of possible funerary function tentatively trace back to the late pre-protohistory up to the roman age. The persistent use of the area across a long-time span corroborates its pivotal location in ancient trans-Saharan connection route