Abstract:
The U.S. Geological Survey (USGS) deployed a sediment trap (McLane PARFLUX 78H) mooring in the northern Gulf of Mexico (27.5 °N and 90.3°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 the mooring cable to enable the collection of deeper dwelling species of planktic foraminifera. The trap contains 21 collection cups that were programmed to rotate every 7 to 14 days (resulting in weekly to biweekly sampling resolution). Upon retrieval, samples were subsequently 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-micron (μm) 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 in its entirety. The counts were then summed. All planktic foraminifers were identified to the species level. This report 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 meter-squared [m2]). The sediment trap mooring is currently deployed, and foraminifera data will be updated as new samples are processed.
Purpose:
Sediment trap studies help scientists better understand the environmental factors (e.g., temperature, salinity, ocean circulation, nutrient supply, etc.) that control the chemical composition, ecology, and life history of planktonic organisms living in the water column. These planktonic organisms, preserved in ocean sediments as microfossils or molecular fossils, can be used to reconstruct oceanographic conditions in the Gulf of Mexico over the past few centuries to the past few millions of years. Scientists at the USGS use a long-running sediment trap (since 2008) in the northern Gulf of Mexico to calibrate foraminifera, biomarker, and other micropaleontological proxies for use in climate reconstructions.
Supplemental_Information:
Field Activity Numbers (FANs) are unique identifiers assigned by the USGS to provide more information about the activities conducted in the field for a study. Refer to the data files for a complete list of associated FANs for this data release. Please visit the Coastal and Marine Geoscience Data System (CMGDS) field activity webpage for more information about each FAN related to this dataset. To view field activity details for any of the datasets included in this data release, replace the FAN (09CEV02) in the following url with the FAN of interest (for example, 10CEV01):
https://cmgds.marine.usgs.gov/fan_info.php?fan=09CEV02. This data release (Reynolds and Richey, 2023) includes data from previously published releases by Reynolds and others (2018) and Richey and others (2019). The raw counts and flux data were withdrawn from those two data releases, as the sediment trap foraminifera flux were incorrectly calculated per 0.5 m2 area instead of 1 m2. The corrected data has been provided in this data release and will continue to be updated as more samples are collected.
Theme:
Theme_Keyword_Thesaurus: USGS Metadata Identifier
Theme_Keyword: USGS:7161c453-b4b2-44b0-ac4a-40a25f1edb38
Theme:
Theme_Keyword_Thesaurus: USGS Thesaurus
Theme_Keyword: marine geology
Theme_Keyword: ecology
Theme_Keyword: geochemistry
Theme_Keyword: protists
Theme_Keyword: plankton
Theme_Keyword: micropaleontology
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: biota
Theme_Keyword: geoscientificInformation
Theme_Keyword: oceans
Theme_Keyword: environment
Place:
Place_Keyword_Thesaurus: Geographic Names Information System (GNIS)
Place_Keyword: Gulf of Mexico
Environment as of metadata creation: macOS Monterey Version 12.6.8 and Microsoft Excel for Mac Version 16.75.2 (230401901).