The measurement and modelling of plumes resulting from deep sea mining of Fe-Mn crusts

Abstract

© Environment Federation Technical Exhibition and Conference, WEFTEC 2014.All right reserved. Seamounts are of great oceanographic interest because of their local and basin-scale influence over ocean systems, their often unique ecosystems, and because they are associated with the formation of ferromanganese (Fe-Mn) crusts. These crusts are rich in some of the rare elements increasingly required for development of renewable technologies, if viable and economical mining strategies can be developed to recover these resources. However, little is known about the potential for sediment (and chemical) plumes caused by deep sea mining to adversely affect the local ecosystem. The literature contains many references to the potential for mining to cause irreversible damage to the ecosystem but these are typically based on assumptions rather than evidence. This paper describes studies undertaken as a part of the MarineE-tech UK funded project, investigating the geochemical processes governing, and environmental issues arising from the mining of, Fe-Mn crusts. In this project innovative monitoring approaches have been developed for monitoring deep sea sediment plumes and these approaches have been applied to the Tropic Seamount in the North East Atlantic. The data set, possibly the first of its kind, involves 21 different experiments and has been used to validate detailed and detailed hydrodynamic and sediment transport models as a basis for a predictive tool for assessing the effects of sediment plumes from deep sea mining. These models have deep sea plumes have been then used as tools for evaluating the potential effects of deep sea mining of the crust.