Intensive surveys were made in an abyssal hill province in the North Atlantic at the northeast edge of the Nares Abyssal Plain, where the general conditions favorable for the formation of manganese nodules prevail, i.e., deep water (2600-3300 fm) and low rate of sediment accumulation. Typically, manganese nodules were observed to be abundant in one spot, and just a short distance away, under conditions which seemed to be the same, the ocean floor was completely devoid of nodules. Efforts to develop effective surveying techniques were very successful, particularly use of Kennecott grabbers and a new PINGERPROBE technique in conjunction with satellite navigation.

From 1983 until 1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions. At the time it was the most extended data compilation on ferromanganese deposits world wide. Initially published in a proprietary format incompatible with present day standards it was jointly decided by AWI and NOAA to transcribe this legacy data into PANGAEA. This transfer is augmented by a careful checking of the original sources when available and the encoding of ancillary information (sample description, method of analysis...) not present in the NOAA-MMS database.

Supplement to: Ewing, Maurice; Shipley, Thomas H; Connary, Stephen D (1973): Intensive survey of a manganese nodule region in the North Atlantic Ocean. In: Phase I Report - Inter-University Program of Research on Ferromanganese Deposits of the Ocean Floor. Seabed Assessment Program, IDOE, NSF, Washington D.C., USA, 187-215