SDP Leg 85 was designed to take advantage of a new hydraulic piston corer (HPC) enabling to recover fairly undisturbed samples from the upper 100 to 300 m and thus to carry out high resolution stratigraphic studies. The JOIDES Ocean Paleoenvironment Panel selected five drill sites, two sites (571 and 572) are in the eastern Pacific, and the three others (573, 574, and 575) form a north-south line that lies at approximately 133°W across the equatorial high productivity zone.

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1989 NOAA-NCEI compiled the NOAA-MMS Marine Minerals Geochemical Database from journal articles, technical reports and unpublished sources from other institutions.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