Deep-Sea Robotic Survey and Data Processing Methods for Regional-Scale Estimation of Manganese Crust Distribution

Manganese crusts (Mn-crusts) are a type of mineral deposit that exists on the surface seamounts and guyots at depths >800 m. We have developed method to efficiently map their distribution using data collected by autonomous underwater vehicles remotely operated vehicles. Volumetric measurements Mn-crusts made high-frequency subsurface sonar 3-D visual mapping instrument mounted these an algorithm estimate Mn-crust combining continuous thickness with exposed area identified in 3-D maps. This is applied from three expeditions Takuyo Daigo seamount ∼1400 m. The transects add ∼11 km length 12 510 m2 mapped. results show 52% surveyed covered mean 69.6 mm. occurrence 69.6 kg/m2 maximum 204 kg/m2 mapped region. consistent estimates samples retrieved area, showing more detailed patterns having significantly lower uncertainty bounds for regional-scale inventory estimation.