What controls the geometry of rocky coasts at the local scale?

Swirad, Z.M.; Rosser, N.J.; Brain, M.J.; Vann Jones, E.C.

Abstract

There is a need to understand the controls on rocky coastal form in order to predict the likely response to climate changes and sea-level rise. Spatial variations in coastal geometry result from inheritance and contemporary processes, notably erosive wave intensity and rock resistance. We studied a 4.2 km long section of coastline (Staithes, North Yorkshire, UK) using LiDAR point cloud data and ortho-photographs. We represented the coast as a series of densely-spaced (25 m) and resampled (0.2 m) 2D cross-sections. GIS-based statistical analysis allowed us to identify relationships between coastal morphology, geology (lithology and rock structure) and wave intensity. We found the following statistically-significant relationships: 1) more intensive waves and weaker rocks are associated with steeper shore platforms, 2) higher platforms and cliff toes are associated with weaker and more variable rocks, and 3) surface roughness increases with greater wave intensity, decreased density of discontinuities and decreased variability of intact rock hardness. However, these relationships are weak, which suggests the potential role of coastal inheritance and/or the need to better represent rock resistance in coastal models.

Citation

Swirad, Z., Rosser, N., Brain, M., & Vann Jones, E. (2016). What controls the geometry of rocky coasts at the local scale?. Journal of coastal research, 75(sp1), 612-616. https://doi.org/10.2112/si75-123.1

• Journal Article Type: Article
• Acceptance Date: Jan 15, 2016
• Online Publication Date: Mar 3, 2016
• Publication Date: 2016-03
• Deposit Date: Mar 21, 2016
• Journal: Journal of Coastal Research
• Print ISSN: 0749-0208
• Electronic ISSN: 1551-5036
• Publisher: Coastal Education and Research Foundation
• Volume: 75
• Issue: sp1
• Pages: 612-616
• DOI: https://doi.org/10.2112/si75-123.1