Searching for prehistoric small-sized graves in complex geoarchaeological conditions: Ayios Vasilios North Cemetery (Peloponnese, Greece)

Abstract

Prehistoric cemeteries are important and unique sources of funerary and social practices from the early stages of civilization, but also a highly challenging environment for geophysical investigation. This study evaluates the results of a Ground Penetrating Radar (GPR) survey for the detection and mapping of simple, small-sized, box-shaped graves, placed at small depths at the Late Bronze Age Ayios Vasilios North Cemetery (Laconia, Peloponnese, Greece). Interpreted grave anomalies allowed post-survey excavations to verify and not miss existent graves, but also led to the exploration of several anomalies that were not graves. We highlight and analyze in detail anomalies possibly related to graves in plan- and profile-view, compare them to real structures from pre- and post-survey excavation findings, and search for solutions for an efficient identification of GPR anomalies with graves and increase of the effectiveness and dependability of GPR for grave searching in complex site conditions, which include strong variations between geological and anthropogenic structure. We propose a procedure for refining grave interpretation that utilizes the results of both initial and advanced processing of 2D and 3D GPR data. The results of our study will benefit the use of GPR as a non-invasive method to search for small-sized graves placed at small depths in complex subsurface conditions and extend GPR use to investigate the organization and function of prehistoric cemetery sites in an intensively used space. Our work enhances the literature relative to geophysical surveying of prehistoric cemeteries, while the methodology discussed in this case study provides a useful tool for cemetery site management.