Manganese nodules and ferromanganese crusts deposited on igneous rocks from the Southern Ocean have been chemically analysed after dessication. Al, Ba, Ca, Co, Cu, Fe, Mg, Mn, Mo, Ni, P, S, Si, Ti, V and Zr were analysed by direct reading on a vacuum optical emission spectrometer. K, Na, Pb, Sr and Zn were determined using an atomic absorption spectrophotometry.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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.