Gulf of Alaska 17,000 Year Isotope Data Davies, M.H.; Mix, A.C.; Stoner, J.S. Davies, M.H. Mix, A.C. Stoner, J.S. Younger Dryas earth science/paleoclimate/paleoceanography (delta 13C,Neogloboquadrina pachyderma sinistral,null,per mil PDB,null,paleoceanography,null,null,N,>150 ¼_x0003_m) earth science/paleoclimate/paleoceanography (delta 18O,Globigerina bulloides,null,per mil PDB,null,paleoceanography,null,null,N,>150 ¼_x0003_m) earth science/paleoclimate/paleoceanography (delta 13C,Uvigerina peregrina,null,per mil PDB,null,paleoceanography,null,null,N,>150 ¼_x0003_m) earth science/paleoclimate/paleoceanography (delta 18O,benthic foraminifer,null,per mil PDB,null,paleoceanography,null,null,N,Nonionella sp. >150 ¼_x0003_m) earth science/paleoclimate/paleoceanography (delta 13C,benthic foraminifer,null,per mil PDB,null,paleoceanography,null,null,N,Nonionella sp. >150 ¼_x0003_m) earth science/paleoclimate/paleoceanography (delta 18O,Neogloboquadrina pachyderma sinistral,null,per mil PDB,null,paleoceanography,null,null,N,>150 ¼_x0003_m) earth science/paleoclimate/paleoceanography (delta 13C,Globigerina bulloides,null,per mil PDB,null,paleoceanography,null,null,N,>150 ¼_x0003_m) earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (delta 18O,Uvigerina peregrina,null,per mil PDB,null,paleoceanography,null,null,N,>150 ¼_x0003_m) earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean (EW0408-85JC>LATITUDE 59.555>LONGITUDE -144.1535) Oxygen isotope data from planktonic and benthic foraminifera, on a high-resolution age model (44 14C dates spanning 17,400 years), document deglacial environmental change on the southeast Alaska margin (59°33.32′N, 144°9.21′W, 682 m water depth). Surface freshening (i.e., δ18O reduction of 0.8‰) began at 16,650 ± 170 cal years B.P. during an interval of ice proximal sedimentation, likely due to freshwater input from melting glaciers. A sharp transition to laminated hemipelagic sediments constrains retreat of regional outlet glaciers onto land circa 14,790 ± 380 cal years B.P. Abrupt warming and/or freshening of the surface ocean (i.e., additional δ18O reduction of 0.9‰) coincides with the Bølling Interstade of northern Europe and Greenland. Cooling and/or higher salinities returned during the Allerød interval, coincident with the Antarctic Cold Reversal, and continue until 11,740 ± 200 cal years B.P., when onset of warming coincides with the end of the Younger Dryas. An abrupt 1‰ reduction in benthic δ18O at 14,250 ± 290 cal years B.P. likely reflects a decrease in bottom water salinity driven by deep mixing of glacial meltwater, a regional megaflood event, or brine formation associated with sea ice. Two laminated opal-rich intervals record discrete episodes of high productivity during the last deglaciation. These events, precisely dated here at 14,790 ± 380 to 12,990 ± 190 cal years B.P. and 11,160 ± 130 to 10,750 ± 220 cal years B.P., likely correlate to similar features observed elsewhere on the margins of the North Pacific and are coeval with episodes of rapid sea level rise. Remobilization of iron from newly inundated continental shelves may have helped to fuel these episodes of elevated primary productivity and sedimentary anoxia. STUDY NOTES: Calibrated foraminiferal radiocarbon dates and stable isotope data from N. pachyderma, G. bulloides, U. peregrina, C. wuellerstorfi, and Nonionella sp. at sub-centennial resolution through the Holocene and most recent glacial termination in the Gulf of Alaska. The depth in core is in cmbsf (equivalent to jumbo core depths + 150 cm). To allow direct comparison to U. peregrina, empirical species corrections of +0.64‰ and +0.1‰ were applied to the δ18O values of C. wuellerstorfi and Nonionella sp., respectively. Similarly, an empirical species correction of −0.2‰ was applied to the δ13C values of C. wuellerstorfi. NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Davies, M.H. Investigator : Mix, A.C. Investigator : Stoner, J.S. 2013-03-18 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/14113 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-wuell.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-plank.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-uvig.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-nonion.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-wuell.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-plank.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-uvig.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-nonion.txt English https://www.ncdc.noaa.gov/paleo/study/14113 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-wuell.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-plank.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-uvig.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/davies2011/davies2011-nonion.txt Davies, M.H., A.C. Mix, J.S. Stoner, J.A. Addison, J. Jaeger, B. Finney, and J. Wiest. 2011. The deglacial transition on the southeastern Alaska Margin: Meltwater input, sea level rise, marine productivity, and sedimentary anoxia. Paleoceanography, 26, PA2223. doi:10.1029/2010PA002051. START YEAR: 17500 cal yr BP * END YEAR: 200 cal yr BP -144.1535 59.555 -144.1535 59.555