This data release is a polygon shapefile representing prospective occurrence regions of ferromanganese crusts and abyssal ferromanganese nodules on the seafloor throughout the global oceans. Polygons represent areas where oceanographic criteria, such as low sedimentation rate and moderate primary productivity, overlap with geologic criteria, including regions with appropriate seafloor morphology for each mineral type, such as seamounts and ridges or abyssal plains. The regions indicate where ferromanganese crusts and abyssal ferromanganese nodules are likely to occur but do not indicate whether minerals have been found in these regions, nor do they indicate the presence of a mineral deposit.