Recent advances of geoinformatics in eastern Mediterranean for cultural resource management

Nikos Papadopoulos, Institute for Mediterranean Studies Foundation for Research and Technology

Keywords:  archaeological knowledge production; Science and Technology Studies; geoinformatics

Introduction
Geoinformatics have given a new dimension and perspective in the domain of archaeological research over the last years. The high resolution geophysical mapping using standard and motorized instrumentation, the innovative satellite recording systems of high spectral and spatial resolution, the use of Geographical Positioning Systems and the improved processing systems of digital images and data processing provide great possibilities in extracting spatial and temporal attributes from thearchaeological sites. The use of three dimensional (3-D) modeling and virtual reality methods aim in the monument representation and the reconstruction of the surrounding environment of the archaeological sites. The combination of the above information within Geographic Information System platforms with other data bases coming from archaeological investigations, environmental information and social-economic models provide valuable results regarding the land use during the ancient times. Integrated applications from different terrestrial and submerged archaeological sites in eastern Mediterranean show the capabilities of geoinformatics and 3-D modeling in cultural resources management.

A new perspective in studying the Ancient Greek Urbanization
The understanding of the ancient Greek city is diachronically altered based on the source material and the changing methodological approaches. The large scale excavations in Miletus, Pergamon, Corinth, Delphes, Corinth and Athens (known as “Big Digs”) of the late nineteenth and early twentieth century by foreign archaeological schools and local archaeological societies in the Eastern Mediterranean contributed a wealth of information regarding the ancient Greek built environment. Hidden street systems, fortification walls and gates, monumental architecture, public and commercial venues were all revealed within a singular urban context (Shanks 1996). A significant diverse in the archaeological practice was noticed after the middle of twentieth century with a shift from large scale excavations to detailed studies of the urban environment with targeted fieldwork, a practice that continues until today (Hoepfner and Schwandner 1994; Haggis 2011).
The project AncientCity (http://ancientcity.ims.forth.gr/el/index.php) proposed a different approach to study the Ancient Greek Urbanization focusing on a more regional basis approaching urban centers in two different regions in the Peloponnese (Manineia, Helis, Heraia. The methodological flowchart included the collection of the historical and scientific material from previous and current archaeological fieldwork projects, the digitization of the available spatial data (maps) and the analysis of high resolution satellite images to recognize residues of the ancient built environment street systems, settlement boundaries and roads connecting the urban centers. Large scalemulti-component geophysical prospection methods were employed to illuminate the hidden into the ground cultural relics.
In 2014 an integrated campaign of satellite remote sensing and geophysical survey at Mantinea in central Peloponnese. The known archaeological features at Mantinea include the well-preserved elliptical fortification walls, approximately 4 km in circumference, the agora and theater at the center. Very little of the remaining urban area inside the fortification walls (~120 hectares) has been explored. The application of feature enhancement algorithms on the high resolution satellite images maximized the detection of subsurface structures. The specific processing procedure managed to outline an extensive system of orthogonal streets showing that the city was a planned settlement. The subsequent survey of the site with large scale geophysical prospection methods using motorized multisensor magnetic techniques verified and enhanced the archaeological information context retrieved from the analysis of the satellite data.
Reconstructing the cultural dynamics of coastal and submerged archaeological sites
Geoinformation technologies have been extensively used for the non-destructive mapping of onshore buried antiquities, thus contributing in the management and promotion of the cultural heritage (Sarris 2015). However, these imaging technologies had so far minimal contribution towards the understanding of the past dynamics in littoral and shallow off-shore environments.
The submerged settlement of Lambayanna(Peloponnese) was first discovered by chance in the summer of 2015 under the framework of collaboration between the University of Geneva, the Swiss Archaeological School and the Greek Ephorate of Underwater Antiquities. The in situ survey and preliminary mapping revealed scattered walls and stones all over the bay as well as fortification walls in the opposite direction of the coastline in a water depth ranging between 1m to 3m. These preliminary results showed parallel stone traces in an almost constant distance of 3.5 m indicating a potential structured and built urban environment (Julien Beck, personal communication).
An integrated exploration composed of RTK-GPS and total station, three-dimensional (3-D) static and dynamic Electrical Resistivity Tomography (ERT) and magnetic gradiometry was used to survey the shallow marine area (<3.5m) covering a marine area of about three hectares. The ERT depth slices up to 1m below the sea floor outlined mainly linear segments related to walls or roads as well as compact resistive regions related either to collapsed remains or gathered piles of rocky material. The magnetic map outlined a number of linear, rectilinear and rectangular anomalies having similar orientation that can be attributed to cultural remains buried below the sandy material of the sea bottom.

Conclusions
The application of novel geo-information methodologies through an integrated platform can be effectively used to address specific archaeological questions in diverse environments. The initiative of AncientCity can act as a model for other archaeological projects across the eastern Mediterranean by incorporating new urban models in order to recalibrate the traditional narratives about the development of the Greek city.
At the same time the possibility to apply well-known methods to un- (or under-) explored archaeological shallow-water contexts was very important from the methodological point of view and for the obtained results. The analysis and integration of the geospatial data managed to complete the picture of the submerged archaeological environment, thus contributing in understanding the usage of the past landscape.Ultimately,theseresultscanberegardedasafirststeptowardsthedevelopmentofaneffectiveinterdisciplinaryresearchmodelthatcouldbeappliedtosimilarsubmerged archaeologicalsurveysincoastalorshallow-waterenvironments.

References
Hoepfner, W., and Schwander E.L. 1994. Kassope, BerichuberAusgrabungeneinerspatklassischenStreifenstadt in Nordwestgriechenland, Haus und StadtimklassischenGriechenland, Wohnen in der klassischen Polis”, Band I, Munchen.
Sarris, Apostolos, ed. 2015. Best Practices of Geoinformatic Technologies for the Mapping of Archaeolandscapes. Oxford: Archaeopress.
Shanks, M. 1996. Classical Archaeology: Experiences of the Discipline. London: Routledge.