Seaward of the Mazagan Escarpment and slope is a band about 50 km wide where structures interpreted as diapirs stand like columns within a pile of sediments about 5 km thick . Dredges and cores from Vema cruise 30-13 and Valdivia cruise West Africa 1979 on the slopes of the most landward of these structural highs, just 10 km from the foot of the escarpment recovered fragments of sheared granite. It was hypothesized that, if this structure were a salt diapir, it might have carried upward very old sediments, dating to the earliest stages of Atlantic evolution, in the Early Jurassic or late Triassic. DSDP Leg 79, sites 544 through 547 were closely located on the structure area.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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