The Mississippi Fan is a broad, arcuate accumulation of Pleistocene deep-water sediments deposited in the eastern Gulf of Mexico. Major objectives for drilling the Mississippi Fan were to place the fan lobes into a time-stratigraphic framework, to determine if the midfan channel is migratory in nature, to establish the lithological characteristics of the acoustical high-amplitude zone present near the bottom of the channel fill, to analyze if sand is transported to the lower fan and in which depositional mode it is emplaced, to confirm or modify existing fan models, and to determine the physical and chemical characteristics of these deep-sea fan deposits. In addition to the nine sites situated on the Mississippi fan, two sites (618 and 619) were occupied on the continental slope off Louisiana in intraslope basins formed as the result of active salt diapirism.
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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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.