COBRA Webinar – September 29, 2026

Deep-Sea Mining Sediment Plumes

Dr. Thomas Peacock (Massachusetts Institute of Technology)

Sediment plumes generated by deep-sea mining activities exhibit complex, multiscale dynamics—from local discharge turbulence near mining equipment to larger-scale transport by ambient ocean currents. These plumes are a critical consideration for environmental impact assessment. Recent field observations have significantly advanced our understanding of these processes. In the Clarion-Clipperton Zone, for example, hydrodynamic nodule collectors generate low-lying turbidity currents that strongly influence the sediment budget and overall plume structure at larger scales. These gravity-driven currents propagate away from collector tracks, deposit sediment locally through sedimentation, and then transition to advection of finer suspended material by ambient ocean currents. Discharge plumes into the water column undergo buoyancy-driven turbulent mixing, dilution, and further transport before settling and mixing through background ocean processes. This presentation reviews the current state of knowledge for plumes from polymetallic nodule, seafloor massive sulfide, and cobalt-crust mining operations by providing an overview of the latest field observations and numerical modeling results, furthermore identifying remaining knowledge and capability gaps.