4 Seismic data analysis

4.1 Reflection data processing

The overall quality of the data is reasonable given the high noise level background in the region, with a CMP fold coverage between 180-220 and a maximum offset of ca. 7 km. The highest quality data were registered on the eastern and in the central part of the profile with numerous shot and receiver gathers exhibiting clear reflectivity and first breaks up to maximum offsets (Figure 3). The western parts of the profile show noisier data due to line position close to a big city and major roads. Generally, reflections are more continuous on some receiver gathers, showing that geophone-ground coupling in the city environment is key to acquiring quality data. For this reason, when possible, processing steps were carried out on receiver gathers. An interesting phenomenon of this dataset is the strong presence of back-scattering of surface-waves in some parts of the profile (Figure 4). Given their clear locations, they are used in this study to complement the interpretation of imaging results.