An open-source approach for the vulnerability assessment of archaeological deposits using GPR data in QGIS

Abstract

Ground-penetrating radar (GPR) is a reliable geophysical method for studying and identifying subsurface archaeological remains. This paper presents an innovative workflow for GPR data processing, designed in the context of the project RESEARCH (Remote Sensing techniques for Archaeology, H2020-MSCA-RISE, 2018 n. 823987) by exploiting the potential of the Geographical Information System (GIS). The RESEARCH project addresses risk assessment procedures for archaeological sites threatened by environmental and anthropogenic pressures, such as land-use change, land movement and soil erosion, and the creation of a Web-GIS Platform capable of automatically performing risk assessment procedures. The risk assessment methodology adopted by the RESEARCH project requires data about the depth of the archaeological deposit (features and layers) and specifically the distance from the ground of its most superficial layer to precisely evaluate the vulnerability of archaeological deposits to threats acting on soil, in particular soil erosion. In this regard, an innovative GIS workflow for GPR data processing has been designed to automatically recognise the depth of an archaeological deposit and assign it a vulnerability rating by working on pixel values. The paper illustrates the specific procedure adopted to automate GPR data processing in the QGIS open-source environment. The developed GIS-based tool was tested in the case study of the Roman town of Falerii Novi (Fabrica di Roma, Lazio, Italy)