Shallow seismic investigations in engineering practice in Belgium

In the last ten to fifteen years, shallow seismic investigations have become standard practice in major geotechnical projects in Belgium. Most of these investigations involved a combined use of different seismic techniques, sometimes implemented with other geophysical methods such as geoelectrical or microgravimetric surface measurements and borehole logging. The objectives of applying seismic techniques were generally twofold: the determination of the structural context of a geotechnical site, with particular attention being paid to possible anomalies, and the evaluation of dynamic elastic properties of the bedrock. Relatively deep seismic investigations, carried out in engineering projects related to the exploitation of geothermal resources, nuclear energy projects (e.g. radioactive waste disposal) or feasibility studies of underground gas storage, fall beyond the scope of this paper.