Seismic Surface Wave Investigation of the Lake Erie Bluffs

Both natural and human activities contribute to bluff erosion along the Lake Erie coastline. Bluff erosion may become problematic over time because structures have been built on the bluff. Many factors contribute to bluff erosion; processes such as wave, ground water, surface water and human activity all play a role. A further understanding of the local geology may aid in identifying areas that are at greater risks of high rates of erosion. Geophysical methods are non-invasive techniques that have been used to investigate the near-surface for more than thirty years. There are several seismic methods used to explore the near-surface and seismic surface wave analysis is one such method. The Multichannel Analysis of Surface Waves (MASW) relies on the use of seismic surface waves, in particular Rayleigh waves, to investigate the upper several meters of the subsurface. The end result of the MASW method is to produce a 2-D shear-wave velocity profile of the subsurface. Because shear-wave velocities give an indication of subsurface material stiffness they may be used to help in understanding near-surface conditions and potential influences on erosion.