During the past decade significant progress has been made in the development
of geophysical techniques designed to resolve problems associated
with the unconsolidated sedimentary layers of the shallow subsurface.
Two of these techniques, the high-resolution seismic reflection and
the ground-penetrating radar (georadar) methods, have the potential
to define the character, size, and geometry of surficial sedimentary
units. In an attempt to determine optimum recording and processing
strategies, seismic and gwradar reflection profiles have been recorded
across a variety of glacial, glaciolacustrine, and glaciofluvial
deposits in Switzerland. At one test location we have also conducted
a pilot 3-D high-resolution seismic reflection survey and at another
we have collected an experimental 3-D gwradar data set. Results of
the 3-D surveys are striking images of the shallow subsurface that
provide many more details and much more reliable information on the
3-D heterogeneities of the shallow subsurface than are afforded by
conventional 2-D data sets; at both 3-D test sites critical geological
features would have been misinterpreted had only limited profile
information been available.