The morphodynamics of shore platforms in a micro-tidal setting: Interactions between waves and morphology

The interactions between waves and morphology on shore platforms were investigated at four platforms located at Kaikoura Peninsula, New Zealand and the Otway coast, Victoria, Australia. Waves were measured over six tidal peaks of a spring tidal sequence at each site during a six month period (February 2007 – July 2007). This paper reports the results of an investigation into the research question: how are waves modified by platform morphology in a micro-tidal setting? Through the investigation of wave interactions on shore platforms it was found that complex hydrodynamic patterns formed on the shore platforms studied. Through direct measurement of waves on the platforms it was found that wave attenuation was not dependent on platform width, but rather influenced by platform gradient and depth of water on the platform. Spectral analysis was used to assess how wave energy was transformed across the platforms. At three of the four platforms investigated, energy gradients formed across the platform with wave energy recorded within the infragravity range.