Mapping the geometry of an aquifer system with a high-resolution reflection seismic profile

A high-resolution P-wave seismic reflection survey was conducted in the area of Lambro Park within the city of Milan (northern Italy). Several high permeability channel sequences were identified and the stratigraphy of the infill was accurately mapped. The seismic signature imaged a previously undefined unit and also established the lateral correlation of some depositional units within the three major aquifer groups along the survey line. The complexity of the acoustic framework and the reduced depth of the source location limited effective elastic-wave generation. The geological setting also caused propagation of strong coherent noise patterns. Further interference, observed in the recorded data, was due to the traffic noise from the nearby highway. The attenuation of the undesired events required the design of specific filters and their multistep implementation. The results of forward modelling based on borehole information and of noise tests were crucial factors in the design of the processing parameters and in the stratigraphic interpretation of the final stacked section.