HYPERSPECTRAL TECHNIQUES AND GIS FOR ARCHAEOLOGICAL
INVESTIGATION
D. Emmolo, V. Franco, M. Lo Brutto, P. Orlando, B. Villa
Dipartimento di Rappresentazione, Universitä di Palermo Viale delle Scienze 90128 Palermo, Italy
bevilla@unipa.it, pietroorlando@dirap.unipa.it
Commission WG VII/4
KEY WORDS: Remote sensing, Archaeology, Cultural Heritage, Hyperspectral, Imagery, GIS.
ABSTRACT:
Aerial photos, both in colour and in black and white, have always been very important tools in archaeological surveys. Sensors,
called hyperspectral, were available on the market for some years: they are able to expand the research beyond the visible area of the
electromagnetic spectrum as far as the thermal infrared too.
The use of these sensors, at first restricted to the applications in the traditional fields of Remote Sensing (such as, for instance,
Botany, Agronomy, Geology, Hydrology), was spreading, in recent years, to some sectors, such as archaeological surveys, which
were unexplored before. The presence of structures and hollows in the top subsurface is likely to cause variations in humidity in the
surface. These variations affect both vegetation, and some physical features of the ground such as thermal conductivity and capacity.
Especially in the first hours of day, you can notice thermal anomalies due to different evaporation. The exam of these anomalies,
carried out by the use of techniques of digital processing of images in the spectrum bands particularly sensitive to the above-
mentioned indicators, enables the photointerpreter to determine possible signs of underground structures of archaeological interest.
The application of the remote sensing in archaeology allows to acquire, with rapidity, a lot of information connected to the territory;
that's the reason why, together with the development of sensors, came out the necessity to take advantage from the potentialities
offered by the GIS to manage, process and file the spatial dates acquired with the remote sensing techniques. In this work, in fact, the
results produced with the image processing technique were implemented in a GIS and were overlaid on the historical and
contemporary maps and on the DEM in order to produce, for each study area, a Prediction map of archaeological finds.
1. INTRODUCTION site of Sofiana. The Roman Villa del Casale was constructed on
the remains of an older villa in the first quarter of the fourth
The spatial nature of archaeological data was recognized since century, probably as the centre of a huge latifundium covering
more than a century and the same archaeology was defined as a the entire surrounding area. How long the villa kept this role is
spatial discipline. The diffusion of GIS inside the archaeological not known, maybe for less that 150 years, but the complex
community happened in the last ten years in order to record, remained inhabited and a village grew around it, named Platia,
process and manage a lot of spatial data acquired using different derived from Palatium. It was damaged, maybe destroyed
methodologies of archaeological researches. Archaeology has during the domination of the Vandals and the Visigoths, but the
adopted since time research methods and analysis instruments buildings remained in use, at least in part, during the Byzantine
typical of scientific sectors as Geophysics, Topography, and Arab period. The site was abandoned for good when a
Photogrammetry and Remote Sensing. Recently especially landslide covered the villa in the 12th century CE, and
Remote Sensing and GIS have taken a great importance. These remaining inhabitants moved to the current location of Piazza
technologies offer, through the overall study of the territory, an Armerina. The existence of the Villa was almost entirely
instrument for studying the relationship between community forgotten (some of the tallest parts have always been above
and belonging territory, processing and integrating the ground) and the area used for cultivation. Pieces of mosaics and
information of different origins collected during researches. some columns were found early in the 19th century, and some
The Remote Sensing, thanks to the diffusion in the market of excavations were carried out later in that century, but Paolo Orsi
sensors called hyperspectral, allows to collect information on performed the first serious excavations in 1929, and later by
physical greatnesses on wide territory areas. The buried Giuseppe Cultrera in 1935-39. The latest major excavations
structures produce anomalies on some physical properties, as were in the period 1950-60 by Gino Vinicio Gentile after which
Thermal Inertia and Thermal Conductivity. The digital image the current cover was built. Andrea Carandini has performed a
processing allows to find these anomalies and permits the few very localised excavations in the 1970s.
photointerpeter to individuate possible tracks of buried Sofiana can be considered as a stopping area betwcen Catania
structures of archaeological interest. In this way it is possible to and Agrigento. The most important discovery was a big thermal
individuate areas on which direct other researches as construction at the Trigona house that was discovered in the IV
geophysics. century, where you can see structures of Augustan origin in
marble and signs of mosaics that were illegally opened that are
2. STUDY AREA contemporary with those of the Casale.
An area in the province of Enna was chosen as test site. This 3. HIPERSPECTRAL DATA ACQUISITION
part of Sicily is characterized by the presence of many
archaeological sites; in particular the experimentation regarded MIVIS (Multispectral Infrared and Visible Imaging
the area around the “Villa del Casale” and the archaeological Spectrometer) airborne system is undoubtedly the most
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