Diffraction stack imaging as a potential tool for detecting underground voids – the case of the ancient copper mines of Timna Valley (Israel)

Detection of subsurface features using geophysical methods is an important component of archaeological research. Most geophysical methods suffer from loss of resolution with depth and are most successful when employed on hyper-shallow targets. We present a novel imaging method that utilizes summation of diffracted seismic energy in the depth domain to image the subsurface and detect areas of material contrasts, which is especially useful for detecting subsurface voids. The diffraction imaging (DI) method was validated in a synthetic case and in two archaeological sites where known ancient tunnels exist and then employed in the ancient copper ore district of Timna Valley (southern Israel). The results demonstrate the feasibility of the DI method to detect ancient underground mining galleries that connected between (now blocked) mining shafts, which in turn constitutes a significant contribution to the study of ancient prospection and mining technologies and related social and historical aspects.