Stable isotope data (d13C and d18O) from benthic foraminifera from IODP Site 323-U1339

Benthic foraminifera were quantitatively identified (>150µm size fraction) in 158 samples from IODP site U1339 on the Umnak Plateau, southeastern Bering Sea collected by Expedition 323 Scientists in 2009. Of 128 samples, benthic foraminifera from 44 were analyzed isotopically. Between two and five tests per species were measured together depending on availability and test mass, yielding 116 measurements across four taxa: Elphidium batialis (number of samples = 44), Uvigerina peregrina (number of samples = 32), Nonionella labradorica (number of samples = 22), and Globobulimina auriculata (number of samples = 18). Measurements were performed at the Oregon State University Stable Isotope Laboratory using a Thermo Finnigan MAT-252 coupled to a Kiel III carbonate device, calibrated against NBS-19 and an internal laboratory standard ("Wiley"). Results are reported relative to Vienna Pee Dee Belemnite (VPDB); analytical precision (1σ) was ±0.03‰ for d13C and ±0.05‰ for d18O. These data were used along with benthic foraminiferal assemblage composition and diagenetic characteristics to reconstruct methane seepage in the Bering Sea across Marine Isotope Stages 7 to 12.