Aerial thermal imaging from UAV in archaeology, a case study: the abandoned medieval town of Montecorvino (Foggia, Italy) - (13TH INTERNATIONAL CONFERENCE ON ARCHAEOLOGICAL PROSPECTION 28 AUGUST - 1 SEPTEMBER 2019 SLIGO - IRELAND) (original) (raw)

2019

Developments in thermographic technology and in the production of more affordable and reliable Unmanned Aerial Vehicles (UAVs) over the last decade have led to a new era for thermal imaging in archaeology. New generation thermal cameras and drones are no longer out of reach for many archaeological projects and can be effectively used for revealing subsurface remains or better understand previous archaeological investigations. Montecorvino is a deserted medieval settlement, located near Volturino (Foggia), in south-eastern Italy. Since 2006, archaeological investigations have been conducted on this site by University of Foggia, Italy (Department of Humanities), under the supervision of Prof. Pasquale Favia and Prof. Roberta Giuliani . In August 2018 a series of infrared (thermal) pictures was acquired on this site by means of a FLIR Vue Pro R drone-mounted thermal camera , flown at different times of day (mostly dawn or dusk). The principle behind this methodology is that archaeological remains under the surface may radiate or absorb heat differently than the nearby ground and this process can be recorded by the thermal camera as a difference in temperature. To obtain good results there should be suffcient contrast in the thermal properties of archaeological features and the soil matrix, also the archaeological materials should be close enough to the surface to be affected by heat flux; and the image should be acquired at a time when such differences are pronounced. Image acquisition has been focused on two main areas of the medieval settlement: east of the motte and bailey castle (including the ditch area) and around the Cathedral. Thermal pictures taken in the first area at dusk show some possible archaeological features north-east of the motte (higher temperature, "positive", mark), where the city walls could join the castle proper and east of the ditch (both "positive" and lower temperature, "negative", marks), where the common people lived (Figures 1-2). Pictures taken around the Cathedral show some features ("positive" marks) that could be related to the settlement's main road (west of the church) and to some structures (east of the church), possibly related to the medieval city's main gate. These data will be useful, starting from the 2019 excavation season, in combination with high resolution aerial photogrammetry, for orienting future excavation strategies at Montecorvino and better understanding the development of this strategically important medieval town in south-eastern Italy. Some excavation trenches will be located in the aerial thermal survey areas, for a verification of the preliminary results. Meanwhile, new aerial thermal survey areas will be located on the archaeological site.