Ferromanganese crust samples were collected via dredge during four oceanographic research cruises to the western equatorial Pacific Ocean. The location (latitude, longitude, depth) and concentrations of 27 major and trace elements in the most recent growth layers of ferromanganese crusts from 57 dredge sites are presented here, as well as select seawater chemistry at each location. These data were used in statistical analyses to determine how oceanographic conditions affect the chemical composition of ferromanganese crusts throughout the region. The changes in ferromanganese crust composition show that modern measurements of these primary oceanographic parameters, as well as paleoceanographic reconstructions, can be used to define regions of interest for FeMn crust exploration.

Ferromanganese crusts were collected via dredge from seamounts within the Tuvalu Exclusive Economic Zone in the Pacific Ocean during cruise RR1310 funded by the National Science Foundation aboard the R/V Roger Revelle in 2013. USGS scientists requested these ferromanganese crust samples from the Oregon State University Marine and Geology Repository where they had been archived. Ferromanganese crust samples were sent to USGS for subsampling and major and trace element geochemical analyses. Major and trace element data and thickness for the ferromanganese crusts as well as location information (latitude, longitude, depth) for each sample are provided here.

Ferromanganese crust and phosphorite minerals were collected using remotely operated vehicles in the Southern California Borderland during two separate research cruises – NOAA Ocean Exploration Trust cruise NA124 onboard the E/V Nautilus in 2020, and Schmidt Ocean Institute cruise FK210726 onboard the R/V Falkor in 2021. Ferromanganese crust and phosphorite samples were described and subsampled for geochemical analysis at the USGS Pacific Coastal and Marine Science Center. Geochemical analyses were completed by outside commercial laboratories, and the results were provided to the USGS. Geochemical data, bulk and layer thickness information, as well as location information (latitude, longitude, depth) for each sample are provided here. The geochemical Borderland work was funded by the Pacific Coastal and Marine Science Center and ship time was funded by NOAA Office of Ocean Exploration and Research (grant number NA19OAR110305).

Ferromanganese crusts, nodules, and hydrothermally altered rocks were collected via dredge within the Amerasia Basin in the Arctic Ocean during USCGC icebreaker Healy cruises HLY0805, HLY0905, and HLY1202 in 2008, 2009, and 2012 respectively. Dredged samples were donated and sent to USGS for subsampling and major and trace element geochemical analyses. Major and trace element data as well as location information (latitude, longitude, depth) for each sample are provided here.

Ferromanganese crusts were collected via dredge from seamounts within the Tuvalu Exclusive Economic Zone in the Pacific Ocean during cruise RR1310 funded by the National Science Foundation aboard the R/V Roger Revelle in 2013. USGS scientists requested these ferromanganese crust samples from the Oregon State University Marine and Geology Repository where they had been archived. Ferromanganese crust samples were sent to USGS for subsampling and x-ray diffraction analyses. Powder x-ray diffraction data for bulk and layer fractions of the ferromanganese crusts are provided here. Location information for the sample is included in each Attribute Definition of this metadata file, as well as in the geochemical data table (Tuvalu_RR1310_FeMn_geochem_data.csv) of this multi-table data release.

This data release compiles element composition data for more than 600 deep-ocean mineral samples from more than 25 research cruises in the Pacific Ocean since 1979 that involved USGS researchers. Deep-ocean mineral sample types encompassed in this data release include ferromanganese crusts, manganese nodules, phosphorites, and hydrothermal minerals. This data release is comprised of both unpublished as well as previously published data and reports and includes analytical methods and instrument detection limits whenever available.

Ferromanganese crusts in the world's oceans may serve as potential sources of metals, such as cobalt and magnesium, valuable to civilian and military industry; these are metals that the United States would otherwise be dependent on foreign sources. Unlike abyssal ferromanganese nodules, which form in areas of low disturbance and high sediment accumulation, ferromanganese crusts have been found to contain three to five times more cobalt than abyssal ferromanganese nodules and can be found on harder, steeper substrates than abyssal plains, which can be too steep for permanent sediment accumulation. Ferromanganese crusts have also been documented on seamounts and plateaus within the U.S. exclusive economic zone in the Pacific and Atlantic Oceans and are therefore of strategic importance to the United States Government as well as to civilian mining and metallurgical industries. A database containing ferromanganese crust occurrences throughout the world's oceans was assembled from published and unpublished sources to provide data gathering and analytical information for these samples. These data provide the digital formatted locations of the sample locations of the U.S. Geological Survey and Scripps Institution Nodule Data Bank (SNDB) from appendixes A and B. These locations from 1986 and earlier are also represented on the maps of Lane and others (1986). > Lane, C.M., Manheim, F.T., Hathaway, J.C., and Ling, T.H., 1986, Station maps of the world ocean-ferromanganese-rust database: U.S. Geological Survey Miscellaneous Field Studies Map, 1869, http://pubs.usgs.gov/mf/1986/1869/

Ferromanganese crusts in the world's oceans may serve as potential sources of metals, such as cobalt and magnesium, valuable to civilian and military industry; these are metals that the United States would otherwise be dependent on foreign sources. Unlike abyssal ferromanganese nodules, which form in areas of low disturbance and high sediment accumulation, ferromanganese crusts have been found to contain three to five times more cobalt than abyssal ferromanganese nodules and can be found on harder, steeper substrates than abyssal plains, which can be too steep for permanent sediment accumulation. Ferromanganese crusts have also been documented on seamounts and plateaus within the U.S. exclusive economic zone in the Pacific and Atlantic Oceans and are therefore of strategic importance to the United States Government as well as to civilian mining and metallurgical industries. A database containing ferromanganese crust occurrences throughout the world's oceans was assembled from published and unpublished sources to provide data gathering and analytical information for these samples. These data provide the digital formatted locations of the sample locations of the U.S. Geological Survey and Scripps Institution Nodule Data Bank (SNDB) from appendixes A and B. These locations from 1986 and earlier are also represented on the maps of Lane and others (1986). > Lane, C.M., Manheim, F.T., Hathaway, J.C., and Ling, T.H., 1986, Station maps of the world ocean-ferromanganese-rust database: U.S. Geological Survey Miscellaneous Field Studies Map, 1869, http://pubs.usgs.gov/mf/1986/1869/

Powder x-ray diffraction data (XRD) for samples are provided in this portion of the data release. Ferromanganese crusts, nodules, coated cobbles, and push core sediments were collected via ROV from seamounts off the coast of Hawaii and within the Papahanaumokuakea Marine National Monument (PMNM) in the Pacific Ocean during E/V Nautilus expeditions NA134 and NA138 in 2021 and 2022, respectively. Samples were sent to USGS for subsampling and x-ray diffraction analyses. Location information for the samples is included in each Attribute Definition of this metadata file, as well as in the geochemical data table (Hawaii_Seamounts_marine_minerals_geochemistry_data.csv) of this multi-table data release.

Ferromanganese crusts in the world's oceans may serve as potential sources of metals, such as cobalt and magnesium, valuable to civilian and military industry; these are metals that the United States would otherwise be dependent on foreign sources. Unlike abyssal ferromanganese nodules, which form in areas of low disturbance and high sediment accumulation, ferromanganese crusts have been found to contain three to five times more cobalt than abyssal ferromanganese nodules and can be found on harder, steeper substrates than abyssal plains, which can be too steep for permanent sediment accumulation. Ferromanganese crusts have also been documented on seamounts and plateaus within the U.S. exclusive economic zone in the Pacific and Atlantic Oceans and are therefore of strategic importance to the United States Government as well as to civilian mining and metallurgical industries. A database containing ferromanganese crust occurrences throughout the world's oceans was assembled from published and unpublished sources to provide data gathering and analytical information for these samples. These data provide the digital formatted locations of the sample locations of the U.S. Geological Survey and Scripps Institution Nodule Data Bank (SNDB) from appendixes A and B. These locations from 1986 and earlier are also represented on the maps of Lane and others (1986). > Manheim, F.T., Lane-Bostwick, C.M., 1989, Chemical composition of ferromanganese crusts in the world ocean: A review and comprehensive database: U.S. Geological Survey Open-File Report 89-020, http://pubs.usgs.gov/of/1989/0020/