Seabed dynamics in a coastal embayment

Abstract

This study focuses on the morphological history of the seabed adjacent to the St. Ives to Padstow Bay coastlines, southwest England. 1931 and2008 bathymetric charts covering the North Cornwall coast were examined using bathymetric change maps and transects. The results here showed that the seabed topography in this region is not static, with patterns of net sediment movement varying spatially across the seabed. Rates of erosion and deposition varied because of the seabed exposure to the diverse rates of higher waves and tidal actions. The variation relates to the relative depths at which waves feel the seabed. Waves are more sensitive at nearshore bathymetry depths less than 20m (and 3.5km offshore) than at offshore. However, the amount of energy and increasing wave height reaching the coastlines have a minor impact on sediment transport rates or morphological modification of the adjacent coastlines and estuaries but allow the erosion potentials.Keywords: bathymetry; change detection; morphodynamics; coastal processes; SWAN; wave propagation; coastal zone; volumetric seabed change; shore-normal transects. Biographical notes: Temitope D. Timothy Oyedotun is an internationally recognised environmental researcher and university tutor. For the last 12 years, he has acquired and developed academic and research interests in diverse academic and research fields -principally in water resources management, river dynamics, fluvial geomorphology, quantitative and spatial analyses, geographic information systems (GIS) and, of recent, estuarine/coastal systems morphodynamics (coastal geomorphology). Years of international academic exposures and training have developed in him a culture of discipline with an ethic of academic entrepreneurship and great scholarship performance. He heads the Research and Concept Unit of AfriGeoServ, a consultancy firm he co-founded.