(Table 3) Oxygen and carbon isotopic record of living (Rose Bengal Stained) benthic foraminifera of North Atlantic surface sediments

• Main Authors: Corliss, Bruce H, McCorkle, Daniel C, Higdon, David M
• Format: Dataset
• Language: English
• Published: PANGAEA 2015
• Subjects: Date/Time of event; Depth; bottom/max; sediment/rock; top/min; Elevation of event; EN281-1; EN281-2; EN281-3; EN284-1; EN284-10; EN284-11; EN284-2; EN284-3; EN284-5; EN284-7; EN284-9; EN289-1; EN289-2; EN289-3; EN293-1; EN293-4; EN293-5; Event label; Hoeglundina elegans; δ13C; δ18O; Latitude of event; Longitude of event; Mass spectrometer Finnigan MAT 252; MUC; MultiCorer; North Atlantic; OC283-2; OC283-3; OC283-4; OC283-6; OC283-7; Planulina wuellerstorfi; Sample code/label; SC; Size fraction; Soil combustion; Uvigerina peregrina; Nantucket; Northwest Atlantic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.844864; https://doi.org/10.1594/PANGAEA.844864

Variation of the d13C of living (Rose Bengal stained) deep-sea benthic foraminifera is documented from two deep-water sites (~2430 and ~3010 m) from a northwest Atlantic Ocean study area 275 km south of Nantucket Island. The carbon isotopic data of Hoeglundina elegans and Uvigerina peregrina from five sets of Multicorer and Soutar Box Core samples taken over a 10-month interval (March, May, July, and October 1996 and January 1997) are compared with an 11.5 month time series of organic carbon flux to assess the effect of organic carbon flux on the carbon isotopic composition of dominant taxa. Carbon isotopic data of Hoeglundina elegans at 3010 m show 0.3 per mil lower mean values following an organic carbon flux maximum resulting from a spring phytoplankton bloom. This d13C change following the spring bloom is suggested to be due to the presence of a phytodetritus layer on the seafloor and the subsequent depletion of d13C in the pore waters within the phytodetritus and overlying the sediment surface. Carbon isotopic data of H. elegans from the 2430 m site show an opposite pattern to that found at 3010 m with a d13C enrichment following the spring bloom. This different pattern may be due to spatial variation in phytodetritus deposition and resuspension or to a limited number of specimens recovered from the March 1996 cruise. The d13C of Uvigerina peregrina at 2430 m shows variation over the 10 month interval, but an analysis of variance shows that the variability is more consistent with core and subcore variability than with seasonal changes. The isotopic analyses are grouped into 100 µm size classes on the basis of length measurements of individual specimens to evaluate d13C ontogenetic changes of each species. The data show no consistent patterns between size classes in the d13C of either H. elegans or U. peregrina. These results suggest that variation in organic carbon flux does not preferentially affect particular size classes, nor do d13C ontogenetic changes exist within the >250 to >750 µm size range ...