Combined Geophysical Survey at the A2 Tunnel Maastricht

In advance of the construction of the A2 tunnel in Maastricht a geophysical survey was necessary in order to investigate the position of layers, faults, flint layers, occurrence of rock deposits and potential cavities within the limestone layer. For this purpose three different geophysical methods were combined: CMP refraction seismic, refraction tomography, reflection seismic. The whole survey was performed with three different sources to get the best results for each depth: air sound source, sledgehammer and accelerated weight drop source. After processing and during the interpretation process the results of 18 boreholes were included. Finally all relevant layers could have been detected and corresponded to the results of drilling. Furthermore minor and major faulting in the survey area could be detected. Potential cavities in the limestone were not detected.