Gulf of Mexico Sediment Trap Foraminifera Data

The U.S. Geological Survey (USGS) deployed a sediment trap (McLane PARFLUX 78H) mooring in the northern Gulf of Mexico (27.5 degrees N and 90.3 degrees W, water depth 1150 meters [m]) in January 2008 to collect seasonal time-series data on the flux and assemblage composition of planktic foraminifers. The trap was positioned in the water column at a depth of 700 m on a mooring cable to enable the collection of deeper dwelling species of planktic foraminifera. The trap contains 21 collection cups that are programmed to rotate every 7 to 14 days (resulting in weekly to biweekly sampling resolution). Sample cups are filled with a high-density buffered solution (salinity ~44 psu) made with formalin (3.7%), sodium borate, and filtered seawater. Samples were wet split into four aliquots using a precision rotary splitter, stored in buffered deionized water, and refrigerated. A quarter split was wet sieved over a 150-micrometer sieve and subsequently wet picked for all foraminifers. In samples containing fewer than 300 foraminifers in the first quarter split, an additional split was processed and picked. The counts were then summed. All planktic foraminifers were identified to the species level.

This data release gives information on the raw counts and foraminifera flux (tests m-2 day-1) through May 2014. Flux was calculated based on the total number of foraminifera for each sub-sample, the fraction of the total sample used, the duration (days) the sediment trap was opened and collecting data for a given sample, and the aperture area of the sediment trap (0.5 m2). The sediment trap mooring is currently deployed, and foraminifera data will be updated when new samples are processed.

Note: This data release contains data previously published at https://doi.org/10.5066/F72806W4 (April 6, 2018) and https://doi.org/10.5066/P9KK7UD6 (February 11, 2019). This data release was published on September 11, 2023, correcting the previously published sediment trap foraminifera flux data by adjusting the calculation from 0.5 m2 area to 1 m2. Please see the Suggested Citation section for details.