Investigation of the application of mechanical mining of ocean floor polymetallic sulphide deposits

This thesis focused on developing and understanding of the challenges of mining subsea polymetallic sulphide (PMS) deposits. The research presented starts from the concept of deposit identification through to prototype testing of an ocean mining excavator. The work presented builds on existing work in the field as well as relying heavily on the Solwara Ocean mining expedition case study carried out in conjunction with Barrick Gold and Nautilus Minerals. The research demonstrates the mechanical cutting of PMS sulphide deposits in the Manus Basin and confirms the viability of mechanical excavation as a mining strategy. As well, knowledge was gained in the performance of an undersea excavator and potential design objectives for a future generation mining ocean machine. This thesis presents the results of 27 cutting dives in the Manus Basin as well as the results from surface cutting trials of PMS substitute materials. The result indicate that excavation of deep ocean PMS deposits is technically viable.Applied Science, Faculty ofMining Engineering, Keevil Institute ofGraduat