- This study focuses specifically on the investigation of a new, inexpensive geophone system and its application to monitor wave activity. Studies of seismic observations of coastal cliffs suggest that ground motions generated from local ocean waves may provide a surrogate to limited wave buoy data to quantify the wave contact and impact on the coastal cliff. Ground motion monitoring of ocean waves also has the potential to improve our understanding of coastal processes by understanding not only how frequently waves impact the coastal cliff but also the accelerations (shaking) present in the cliff as a result of the impact. A preliminary test was conducted using the GeoMoteShield geophone system at varying gain settings (4, 8 and 16 x gain levels) with three sensors located at different distances from the bluff face. The results imply that the degree of ground motion detected is dependent on a variety of parameters: distance from the bluff, the magnitude of wave energy etc. When tidal and significant wave height levels measured from a nearby buoy were larger, a stronger correlation was observed between the amplitude
recorded at the sensors compared with the significant wave height. There is also a correlation between the system’s ability to predict wave action and the sensors proximity to the cliff top edge. Sensors placed too far from the cliff’s edge were affected too much by ambient traffic sounds.