Gulf of Alaska 17,000 Year Paleoproductivity Data Addison, J.A.; Finney, B.P.; Dean, W.E.; Davies, M.H.; Mix, A.C.; Stoner, J.S.; Jaeger, J.M. Addison, J.A. Finney, B.P. Dean, W.E. Davies, M.H. Mix, A.C. Stoner, J.S. Jaeger, J.M. Younger Dryas earth science/paleoclimate/paleoceanography (depth,null,null,centimeter,null,paleoceanography,composited,null,N,null) earth science/paleoclimate/paleoceanography (cobalt,sediment,null,parts per million,null,paleoceanography,null,inductively-coupled plasma atomic emission spectroscopy|inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (molybdenum,sediment,null,parts per million,null,paleoceanography,null,inductively-coupled plasma atomic emission spectroscopy|inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (nitrogen,sediment,null,weight percent,null,paleoceanography,null,elemental analysis,N,null) earth science/paleoclimate/paleoceanography (age,null,null,calendar kiloyear before present,null,paleoceanography,null,null,N,null) earth science/paleoclimate/paleoceanography (organic carbon,sediment,null,weight percent,null,paleoceanography,null,elemental analysis,N,null) earth science/paleoclimate/paleoceanography (delta 15N,sediment,null,per mil,null,paleoceanography,null,isotope ratio mass spectrometry,N,carbonate-free sample) earth science/paleoclimate/paleoceanography (carbonate,sediment,null,weight percent,null,paleoceanography,null,carbon coulometry|inductively-coupled plasma atomic emission spectroscopy,N,null) earth science/paleoclimate/paleoceanography (uranium,sediment,null,parts per million,null,paleoceanography,null,inductively-coupled plasma atomic emission spectroscopy|inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (delta 15N,sediment,null,per mil,null,paleoceanography,corrected,isotope ratio mass spectrometry,N,carbonate-free sample) earth science/paleoclimate/paleoceanography (manganese,sediment,null,parts per million,null,paleoceanography,null,inductively-coupled plasma atomic emission spectroscopy|inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (biogenic silica,sediment,null,weight percent,null,paleoceanography,null,spectrophotometry,N,null) earth science/paleoclimate/paleoceanography (delta 13C,organic matter,null,per mil,null,paleoceanography,null,isotope ratio mass spectrometry,N,carbonate-free sample) earth science/paleoclimate/paleoceanography (chromium,sediment,null,parts per million,null,paleoceanography,null,inductively-coupled plasma atomic emission spectroscopy|inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (aluminum,sediment,null,weight percent,null,paleoceanography,null,inductively-coupled plasma atomic emission spectroscopy|inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleoceanography (cadmium,sediment,null,parts per million,null,paleoceanography,null,inductively-coupled plasma atomic emission spectroscopy|inductively-coupled plasma mass spectrometry,N,null) earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean earth science/paleoclimate/paleocean (EW0408-85JC>LATITUDE 59.555>LONGITUDE -144.1535) Biogenic opal, organic carbon, organic matter stable isotope, and trace metal data from a well-dated, high-resolution jumbo piston core (EW0408-85JC; 59°33.3'N, 144°9.21'W, 682 m water depth) recovered from the northern Gulf of Alaska continental slope reveal changes in productivity and nutrient utilization over the last 17,000 years. Maximum values of opal concentration (~10%) occur during the deglacial Bølling-Allerød (B-A) interval and earliest Holocene (11.2 to 10.8 cal ka BP), moderate values (~6%) occur during the Younger Dryas (13.0 to 11.2 cal ka BP) and Holocene, and minimum values (~3.5%) occur during the Late Glacial Interval (LGI). When converted to opal mass accumulation rates, the highest values (~5000 g cm-2 kyr-1) occur during the LGI prior to 16.7 cal ka BP, which points to a strong influence by LGI glaciomarine sedimentation regimes. Similar patterns are also observed in total organic carbon and cadmium paleoproductivity proxies. Mid-Holocene peaks in the terrestrial organic matter fraction at 5.5, 4.7, 3.5, and 1.2 cal ka BP indicate periods of enhanced delivery of glaciomarine sediments by the Alaska Coastal Current. The B-A and earliest Holocene intervals are laminated, and enrichments of redox-sensitive elements suggest dysoxic-to-anoxic conditions in the water column. The laminations are also associated with mildly enriched sedimentary d15N ratios, indicating a link between productivity, nitrogen cycle dynamics, and sedimentary anoxia. After applying a correction for terrestrial d15N contributions based on end-member mixing models of terrestrial and marine organic matter, the resulting B-A marine d15N (6.3 ± 0.4 ‰) ratios are consistent with either mild denitrification, or increased nitrate utilization. These findings can be explained by increased micronutrient (Fe) availability during episodes of rapid rising sea level that released iron from the previously subaerial coastal plain; iron input from enhanced terrestrial runoff; and/or the intermittent presence of seasonal sea ice resulting from altered ocean/atmospheric circulation during the B-A in the Gulf of Alaska. STUDY NOTES: Multiproxy sediment paleoproductivity data from a jumbo piston core collected on the northern Gulf of Alaska continental slope. Proxy data measured include biogenic opal, organic carbon, organic matter stable isotopes, and trace metal data. These organic and inorganic geochemical data are from the northern continental slope of the Gulf of Alaska, and span from 1.1 to 17.4 calibrated kyrs ago. This marine sediment record is continuous and well-dated by 37 AMS radiocarbon dates on planktonic foraminifera (see Davies et al., 2011 for further information). Opal was measured by a 0.1 M NaCO3 extraction and a molybdate-blue spectrophotometric method (Mortlock and Froehlich, 1989). Total organic carbon (TOC) and total nitrogen (TN) were measured on a carbonate-free subsample by combustion in a Costech 4010 HCNS elemental analyzer. Organic matter d13C and sedimentary d15N were measured on a carbonate-free subsample using a Finnigan Delta-plus XP isotope ratio mass spectrometer. CaCO3 data is a combination of total Ca measured by ICP-OES (n = 110), calibrated with a smaller number of CaCO3 coulometric measurements (n = 43). Inorganic element concentrations (Al, Mn, Co, Cr, U, Mo, and Cd) were measured by a combination of ICP-OES and ICP-MS at SGS Minerals Services in Toronto, Canada. A terrestrial-N-corrected dataset of sedimentary d15N is also included. This data reflects the application of a linear endmember mixing model between terrestrial and marine organic matter to remove the influence of terrestrial N from the bulk sedimentary d15N measurements. These data should be considered on a qualitative basis only. Please see Addison et al. (2012) or contact the author directly for further information. Core EW0408-85JC: 59°33.3'N, 144°9.21'W, 682 m water depth NCDC-Paleoclimatology https://www.ncdc.noaa.gov/data-access/paleoclimatology-data - Bauer Bruce Investigator : Addison, J.A. Investigator : Finney, B.P. Investigator : Dean, W.E. Investigator : Davies, M.H. Investigator : Mix, A.C. Investigator : Stoner, J.S. Investigator : Jaeger, J.M. 2012-08-01 ONLINE Files online, ASCII https://www.ncdc.noaa.gov/paleo/study/13180 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/addison2012/addison2012.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/addison2012/addison2012.txt https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/addison2012/addison2012.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/addison2012/addison2012.txt English https://www.ncdc.noaa.gov/paleo/study/13180 https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/addison2012/addison2012.xls https://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/addison2012/addison2012.txt Addison, J.A., B.P. Finney, W.E. Dean, M.H. Davies, A.C. Mix, J.S. Stoner, and J.M. Jaeger. 2012. Productivity and sedimentary d15N variability for the last 17,000 years along the northern Gulf of Alaska continental slope. Paleoceanography, Vol. 27, PA1206, doi:10.1029/2011PA002161. START YEAR: 17394 cal yr BP * END YEAR: 1085 cal yr BP -144.1535 59.555 -144.1535 59.555