oa Shallow 3-D reflection seismic surveying of glacial sediments in the Swiss molasse basin

Applications of geophysical methods to resolve diverse engineering and environmental problems have become increasingly common over the past few years. Investigations of shallow targets in complex heterogeneous geological settings require methods capable of providing high-resolution infonnation. Although seismic reflection profihing has often been applied successfully in nearsurface studies, reliable knowledge of the true dip and lateral extent of structures cannot be obtained from sparse 2-D seismic data sets alone (Lanz et al., 1996). In order to map the stratigraphy and three-dimensional distribution of unconsolidated surficial sediments a 3-D highresolution reflection seismic survey has recently been conciucted within the Suhre Valley, central Switzerland.