Piper et al.(1987)による〔『Distribution of ferromanganese nodules in the Pacific Ocean』(171p)から〕


 The distribution of ferromanganese nodules in the Pacific Ocean has been determined from bottom photographs, taken at about 2.500 stations, and from sediment cores. Nodule coverage of the seafloor is variable, as much as 75% at a single photographic station for which 850 photos were taken over a distance of approximately 2.5 km. The average nodule coverage for each of the 2,500 stations, however, indicates high seafloor coverage in the following five large areas: (1) between the Clarion and Clipperton Fracture Zones in the Northeast Pacific Basin extending westward into the northern area of the Central Pacific Basin; (2) the area of the Musicians Seamounts also in the Northeast Pacific Basin; (3) the central part of the Southwest Pacific Basin; (4) an east-west trending belt in the southern ocean along 60゜S at the Antarctic convergence; and (5) the northern part of the Peru Basin. This pattern correlates strongly with that of the sediment lithology and sediment accumulation rates. With a few notable exceptions, nodules tend to be restricted in their occurrence to areas of either pelagic clay or biosiliceous clay/ooze, and to areas exhibiting sedimentation rates less than approximately 5 mm/1,000 years. Their occurrence may also be governed by the abyssal circulation of the Pacific. 』

With 4 Figures and 2 Plates an Appendix

References cited