PhD: Bedload transport of sediment mixtures in shelf seas
School of Ocean Sciences
Email Connor McCarron
I am from Derry~Londonderry in Northern Ireland where I originally studied BSc (Hons) Marine Science at the University of Ulster. During my undergraduate studies I gained an interest in the use of geophysical techniques for the discrimination of seabed features and processes which was the basis of my undergraduate thesis. At the end of my studies I worked as an assistant scientific officer and a research support technician at the Loughs Agency before moving to Wales to study MSc Applied Marine Geoscience at the School of Ocean Sciences, Bangor University. Since my return to education my interest and knowledge of offshore geophysical techniques has improved and in my master’s thesis I investigated the morphodynamic and sedimentary impacts on the seabed due to aggregate extraction. I have now began my PhD at Bangor University through which I am investigating shelf seabed morphodynamics in mixed sediments in an attempt to improve the current understanding of bedload sediment transport processes.
This research is important as the morphology of the seabed is controlled primarily by prevailing hydrodynamic regimes (i.e. waves, tides and currents) and subsequently bedload sediment transport. The UK’s shelf seas are comprised of mixed sediments (i.e. sand and gravel) due to the deposition of reworked sedimentary material by paleo-glacial processes. The presence of a range of grain size fractions is thought to impose a “hiding-exposure” effect where smaller grains are sheltered or “hidden” by larger, more “exposed” grains. This changes the efficiency of the flow to mobilise different grain size fractions affecting bedload transport and in turn seabed morphodynamics. The current methods used to predict bedload transport, however, do not incorporate these effects which may reduce the ability to accurately predict seabed morphology and development. Therefore, an improvement in the current understanding of these processes will have wide implications for fields such as paleo-environment reconstruction, habitat mapping, offshore development, aggregate extraction, coastal protection and the prediction of carbon or pollutant fluxes which depend on the ability to predict the mobility of sediments and the resulting seabed morphology.