Seismic signatures of individual wave impacts on a coastal cliff

The mechanisms through which wave action induces cliff erosion are not well quantified, limits our ability to model future erosion. Previous studies have investigated using seismic measurements of cliff-top ground motion from impacts as a proxy for potential driven However, most attention has focussed on averaged hourly statistics, rather than at the individual impact scale. Higher temporal resolution needed determine extent frequent, low magnitude transfer energy into rock, compared violent that occur much less frequently. We carried out fieldwork in Taranaki, New Zealand is exposed broken, breaking, and unbroken different tidal stages. Synchronized seismometer, gauge, video data were collected observe range types under marine conditions. Approximately 7500 manually classified eight groups according stage transformation data. Corresponding signals then analysed compare types. greatest peaks associated with classes identifiable by breaking just front of, or onto face. Waves classed broken had median displacement 4.2 μm 5.1 μm, respectively, whereas value 25.8 μm. Spectral analyses suggest produce frequency bands, total higher classes. This research provides first step assessing spectral signature an scale, providing new method investigate wave–cliff interaction.