Detection of lateral discontinuities via surface waves analysis: A case study at a derelict industrial site

Abstract

We applied a multi-offset surface wave analysis (MOPA) to detect subsoil lateral heterogeneities at a dismissed industrial site along the coast of the city of Trieste (Italy). The site is heavily contaminated and is undergoing characterization in view of possible remediation and re-use. Sea/land interactions and massive anthropic interventions make the site particularly complex. The main lateral heterogeneities consist of an extended buried quay, which also divides continental and marine sediments. We used seismic surface waves to define this contact, while also using supporting data from boreholes and geo-electrical surveys. A multi-offset phase and attenuation analysis was conducted on a few seismic lines, and produced clear evidence concerning the sought heterogeneities. Field data interpretation was corroborated also by ancillary information, and by synthetic modeling, that produced seismograms totally consistent with the recorded ones. In summary, the case study demonstrates how MOPA can be applied in a straightforward manner to define heterogeneities even at a very small spatial scale, and in complex environments such as derelict industrial sites.