Geophysical Prospection of Archaeological Sites on the Northern Peloponnese, Greece: Geological and Urban Challenges

Despite 20 years of many developments, challenges remain for geophysical prospection of archaeological sites; two of these challenges are investigated in this thesis on case studies from the archaeological sites Aigeira and Sikyon; the geological setting and urban environments. These challenges can be overcome through various multi-method approaches depending on the region as shown on a series of case studies. However, this work also includes an extensive multi-method geophysical study focused on an enigmatic subsurface structure that could be interpreted as either prehistoric chamber tombs or complex, highly heterogeneous weathering patterns. This work demonstrates how shear-wave seismics and full-waveform inversion (FWI) can be used in archaeological prospecting to distinguish between different interpretive models. Since it is able to reveal a highly heterogeneous subsurface that is characterized by linear cracks on a decimeter scale. The second main case study highlights the challenge of a large-scale seismic prospection in an urban area. Even in the urban environment of modern Kiato, active seismic surveys in search of Sikyon's silted-up harbor basin have, in principle, been successfully conducted. Due to the too disturbing factors of the urban environment, passive ambient noise recording methods were tested. This thesis shows that the horizontal-to-vertical spectral ratio (HVSR) method can be used as a substitute of refraction seismics to map the depth of the first layer interface over large areas after establishing a relationship between the HVSR resonance frequency and refractor depth. The analysis of arrays (beamforming) of very small aperture arrays consisting of 9 stations proved capable to image the subsurface in similar resolution as does MASW. Hence, this method can be seen as a substitute to the Love-wave analysis for determining shear-wave velocities in an urban environment