# Biogenic Silica Data from the Indian Ocean sector of the Southern Ocean during the mid-Pleistocene climate transition #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program #----------------------------------------------------------------------- # Template Version 3.0 # Encoding: UTF-8 # NOTE: Please cite original publication, online resource and date accessed when using this data. # If there is no publication information, please cite Investigator, title, online resource and date accessed. # # Description/Documentation lines begin with # # Data lines have no # # # Online_Resource: https://www.ncdc.noaa.gov/paleo/study/24090 # Description: NOAA Landing Page # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/billups2018/billups2018-745b.txt # Description: NOAA location of the template # # Archive: Paleoceanography # # Dataset_DOI: # # Parameter_Keywords: geochemistry #--------------------------------------- # Contribution_Date # Date: 2018-05-16 #--------------------------------------- # File_Last_Modified_Date # Date: 2018-05-16 #--------------------------------------- # Title # Study_Name: Biogenic Silica Data from the Indian Ocean sector of the Southern Ocean during the mid-Pleistocene climate transition #--------------------------------------- # Investigators # Investigators: Billups, Katharina; York, Kelsee; Bradtmiller, Louisa I. #--------------------------------------- # Description_Notes_and_Keywords # Description: #--------------------------------------- # Publication # Authors: Billups, K., K. York, and L.I. Bradtmiller # Published_Date_or_Year: 2018 # Published_Title: Water column stratification in the Antarctic zone of the Southern Ocean during the mid-Pleistocene climate transition # Journal_Name: Paleoceanography and Paleoclimatology # Volume: 33 # Edition: # Issue: # Pages: # Report_Number: # DOI: 10.1029/2018PA003327 # Online_Resource: # Full_Citation: # Abstract: We use biogenic silica (opal) mass accumulating rates (MARs) at Ocean Drilling Program Site 745B to infer upwelling, and by extension upper water column stratification, on glacial to interglacial time scales during the mid-Pleistocene climate transition (MPT; 1.2–0.6 Ma). Distinct variations in the percent biogenic silica content of the sediments parallel the global benthic foraminiferal d18O stack affording the derivation of an orbital-scale age model. Opal MARs confirm that silica production/preservation was indeed at a minimum at each of the glacial maxima during the entire MPT consistent with the late Pleistocene model that links upwelling of dissolved silica with water column stratification. A unique relationship between opal MARs and benthic foraminiferal d13C values in the South Atlantic suggests that during the midpoint of the MPT stratification may also be causally related to deep water circulation. However, there is no evidence that cooling during the MPT and the evolution of the 100 kyr climate cycle are linked to changes in water column stratification. Terrigenous sediment MARs, on the other hand, which can be inferred from the proportion of biogenic silica in the sediments at this particular site, provide evidence for increased glacial activity on Antarctica beginning with the onset of the MPT and culminating in a maximum during its midpoint (Marine Isotope Stage 22, 0.9 Ma). Thereafter, glacial activity decreases and we speculate that the evolution of the 100 kyr cycle is associated with a thickening ice sheet after reaching maximum extent somewhat analogous to the processes proposed for Northern Hemisphere ice sheets. #--------------------------------------- # Funding_Agency # Funding_Agency_Name: # Grant: #--------------------------------------- # Site_Information # Site_Name: ODP 745B # Location: Indian Ocean # Country: # Northernmost_Latitude: -59.616667 # Southernmost_Latitude: -59.616667 # Easternmost_Longitude: 86.866667 # Westernmost_Longitude: 86.866667 # Elevation: -4082 #--------------------------------------- # Data_Collection # Collection_Name: ODP745B silica Billups2018 # First_Year: 1093000 # Last_Year: 643000 # Time_Unit: cal yr BP # Core_Length: # Notes: #--------------------------------------- # Chronology_Information # Chronology: #--------------------------------------- # Variables # Data variables follow that are preceded by "##" in columns one and two. # Variables list, one per line, shortname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) ## Site notes,,,,,paleoceanography,,,N,site ## Hole notes,,,,,paleoceanography,,,C,hole ## Core notes,,,,,paleoceanography,,,C,core ## Section notes,,,,,paleoceanography,,,N,section ## top depth at sample start,,,centimeter,,paleoceanography,,,N,depth at top of core section ## bottom depth at sample end,,,centimeter,,paleoceanography,,,N,depth at bottom of core section ## mbsf depth,,,meter,,paleoceanography,,,N,below sea floor ## Age_Ogg age,,,million years ago,,paleoceanography,,,N,based on magnetostratigraphy using the ages of Ogg et al. (2012) ## Age_LR age,,,million years ago,,paleoceanography,,,N,based on tuning of the biogenic silica to the d18O stack of Lisiecki and Raymo (2005) ## Biogenic_silica Biogenic silica,sediment,,percent,,paleoceanography,,spectrophotometry,N, #------------------------ # Data # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing_Values: Site Hole Core Section top bottom mbsf Age_Ogg Age_LR Biogenic_silica 745 B 5H 1 8 9 33.58 0.651 0.643 28.4 745 B 5H 1 18 20 33.68 0.653 0.645 26.4 745 B 5H 1 28 30 33.78 0.655 0.647 26.8 745 B 5H 1 38 40 33.88 0.657 0.649 35.9 745 B 5H 1 48 50 33.98 0.659 0.651 35.8 745 B 5H 1 58 60 34.08 0.661 0.653 37.9 745 B 5H 1 68 70 34.18 0.663 0.655 35.2 745 B 5H 1 78 80 34.28 0.665 0.657 35.5 745 B 5H 1 88 90 34.38 0.667 0.659 36.4 745 B 5H 1 98 100 34.48 0.669 0.661 36.4 745 B 5H 1 108 110 34.58 0.671 0.663 40.5 745 B 5H 1 118 120 34.68 0.673 0.665 38.3 745 B 5H 1 128 130 34.78 0.676 0.667 40.0 745 B 5H 1 138 140 34.88 0.678 0.669 39.0 *745 B 5H 2 0 1 35.00 0.680 0.671 42.6 745 B 5H 2 8 10 35.08 0.682 0.673 43.3 745 B 5H 2 18 20 35.18 0.684 0.675 42.7 745 B 5H 2 28 30 35.28 0.686 0.677 43.1 745 B 5H 2 38 40 35.38 0.688 0.679 42.0 745 B 5H 2 48 50 35.48 0.690 0.681 37.9 745 B 5H 2 58 60 35.58 0.692 0.683 44.5 745 B 5H 2 68 70 35.68 0.694 0.685 47.3 745 B 5H 2 78 80 35.78 0.696 0.687 51.1 745 B 5H 2 88 90 35.88 0.698 0.689 50.9 745 B 5H 2 98 100 35.98 0.700 0.691 53.1 745 B 5H 2 108 110 36.08 0.702 0.693 56.4 745 B 5H 2 118 120 36.18 0.704 0.695 56.0 745 B 5H 2 128 130 36.28 0.706 0.697 57.2 745 B 5H 2 138 140 36.38 0.709 0.699 54.0 745 B 5H 2 148 150 36.48 0.711 0.701 51.4 745 B 5H 3 8 10 36.58 0.713 0.705 48.7 745 B 5H 3 18 20 36.68 0.715 0.708 45.8 745 B 5H 3 28 30 36.78 0.717 0.712 39.6 745 B 5H 3 38 40 36.88 0.719 0.716 43.1 745 B 5H 3 48 50 36.98 0.721 0.719 36.9 745 B 5H 3 58 60 37.08 0.723 0.723 26.8 745 B 5H 3 68 70 37.18 0.725 0.726 34.8 745 B 5H 3 78 80 37.28 0.727 0.730 43.9 745 B 5H 3 88 90 37.38 0.729 0.734 43.9 745 B 5H 3 98 100 37.48 0.731 0.738 39.8 745 B 5H 3 108 110 37.58 0.733 0.743 25.3 745 B 5H 3 118 120 37.68 0.735 0.747 26.7 745 B 5H 3 128 130 37.78 0.737 0.752 28.1 745 B 5H 3 138 140 37.88 0.739 0.755 26.0 745 B 5H 3 148 150 37.98 0.741 0.758 29.5 745 B 5H 4 8 10 38.08 0.743 0.761 29.7 745 B 5H 4 18 20 38.18 0.745 0.764 29.1 745 B 5H 4 28 30 38.28 0.747 0.767 31.6 745 B 5H 4 38 40 38.38 0.749 0.771 34.6 745 B 5H 4 48 50 38.48 0.751 0.774 36.2 745 B 5H 4 58 60 38.58 0.753 0.777 41.5 745 B 5H 4 68 70 38.68 0.755 0.780 43.5 745 B 5H 4 78 80 38.78 0.757 0.783 39.6 745 B 5H 4 88 90 38.88 0.759 0.785 36.1 745 B 5H 4 98 100 38.98 0.761 0.788 38.4 745 B 5H 4 108 110 39.08 0.763 0.790 33.0 745 B 5H 4 118 120 39.18 0.765 0.792 19.6 745 B 5H 4 128 130 39.28 0.767 0.794 20.3 745 B 5H 4 138 140 39.38 0.769 0.796 16.5 745 B 5H 4 148 150 39.48 0.771 0.798 23.1 745 B 5H 5 8 10 39.58 0.773 0.800 23.9 745 B 5H 5 18 20 39.68 0.776 0.802 22.2 745 B 5H 5 28 30 39.78 0.778 0.803 23.5 745 B 5H 5 38 40 39.88 0.780 0.805 26.1 745 B 5H 5 48 50 39.98 0.782 0.807 23.1 745 B 5H 5 58 60 40.08 0.784 0.809 34.1 745 B 5H 5 68 70 40.18 0.786 0.811 39.4 745 B 5H 5 78 80 40.28 0.788 0.812 38.5 745 B 5H 5 88 90 40.38 0.790 0.814 39.0 745 B 5H 5 98 100 40.48 0.792 0.816 39.0 745 B 5H 5 108 110 40.58 0.794 0.818 36.8 745 B 5H 5 118 120 40.68 0.796 0.819 37.9 745 B 5H 5 128 130 40.78 0.798 0.821 37.1 745 B 5H 5 138 140 40.88 0.800 0.823 37.3 745 B 5H 5 148 150 40.98 0.802 0.825 34.5 745 B 5H 6 8 10 41.08 0.804 0.826 33.2 745 B 5H 6 18 20 41.18 0.806 0.828 33.5 745 B 5H 6 28 30 41.28 0.808 0.830 33.0 745 B 5H 6 38 40 41.38 0.810 0.832 25.6 745 B 5H 6 48 50 41.48 0.812 0.833 25.8 745 B 5H 6 58 60 41.58 0.814 0.835 47.9 745 B 5H 6 68 70 41.68 0.816 0.837 49.1 745 B 5H 6 78 80 41.78 0.818 0.839 41.2 745 B 5H 6 88 90 41.88 0.820 0.840 26.8 745 B 5H 6 98 100 41.98 0.822 0.842 21.7 745 B 5H 6 108 110 42.08 0.824 0.844 20.4 745 B 5H 6 118 120 42.18 0.826 0.846 18.5 745 B 5H 6 128 130 42.28 0.828 0.847 20.4 745 B 5H 6 138 140 42.38 0.830 0.849 18.8 745 B 5H 6 148 150 42.48 0.832 0.851 19.3 745 B 5H 7 8 10 42.58 0.834 0.852 17.6 745 B 5H 7 18 20 42.68 0.836 0.854 13.0 745 B 5H 7 28 30 42.78 0.838 0.856 28.7 745 B 5H 7 38 40 42.88 0.840 0.858 29.7 745 B 6H 1 8 10 43.08 0.845 0.861 25.8 745 B 6H 1 18 20 43.18 0.847 0.863 24.0 745 B 6H 1 28 30 43.28 0.849 0.865 21.9 745 B 6H 1 38 40 43.38 0.851 0.867 37.3 745 B 6H 1 48 50 43.48 0.853 0.869 25.2 745 B 6H 1 58 60 43.58 0.855 0.870 25.9 745 B 6H 1 68 70 43.68 0.857 0.872 22.4 745 B 6H 1 78 80 43.78 0.859 0.874 11.5 745 B 6H 1 88 90 43.88 0.861 0.876 10.6 745 B 6H 1 98 100 43.98 0.863 0.877 12.3 745 B 6H 1 108 110 44.08 0.865 0.879 9.6 745 B 6H 1 118 120 44.18 0.867 0.881 16.1 745 B 6H 1 128 130 44.28 0.870 0.883 19.7 745 B 6H 1 138 140 44.38 0.872 0.885 22.6 745 B 6H 1 148 150 44.48 0.874 0.887 25.8 745 B 6H 2 8 10 44.58 0.876 0.889 23.2 745 B 6H 2 18 20 44.68 0.878 0.891 19.3 745 B 6H 2 28 30 44.78 0.880 0.893 20.3 745 B 6H 2 38 40 44.88 0.882 0.895 17.5 745 B 6H 2 48 50 44.98 0.884 0.896 18.9 745 B 6H 2 58 60 45.08 0.886 0.898 24.7 745 B 6H 2 68 70 45.18 0.888 0.900 26.9 745 B 6H 2 78 80 45.28 0.890 0.902 26.3 745 B 6H 2 88 90 45.38 0.892 0.904 25.6 745 B 6H 2 98 100 45.48 0.894 0.906 25.5 745 B 6H 2 108 110 45.58 0.896 0.908 20.2 745 B 6H 2 118 120 45.68 0.898 0.910 18.3 745 B 6H 2 128 130 45.78 0.900 0.912 26.6 745 B 6H 2 138 140 45.88 0.902 0.913 26.6 745 B 6H 2 148 150 45.98 0.904 0.915 20.6 745 B 6H 3 8 10 46.08 0.906 0.917 18.4 745 B 6H 3 18 20 46.18 0.908 0.919 22.0 745 B 6H 3 28 30 46.28 0.911 0.921 20.4 745 B 6H 3 38 40 46.38 0.913 0.923 18.7 745 B 6H 3 48 50 46.48 0.915 0.925 20.9 745 B 6H 3 58 60 46.58 0.917 0.927 27.3 745 B 6H 3 68 70 46.68 0.919 0.929 30.1 745 B 6H 3 78 80 46.78 0.921 0.930 29.7 745 B 6H 3 88 90 46.88 0.923 0.932 26.7 745 B 6H 3 98 100 46.98 0.925 0.934 30.8 745 B 6H 3 108 110 47.08 0.927 0.936 30.9 745 B 6H 3 118 120 47.18 0.929 0.938 26.4 745 B 6H 3 128 130 47.28 0.931 0.940 26.5 745 B 6H 3 138 140 47.38 0.933 0.942 26.2 745 B 6H 3 148 150 47.48 0.935 0.944 23.3 745 B 6H 4 8 10 47.58 0.937 0.945 21.0 745 B 6H 4 18 20 47.68 0.939 0.947 17.4 745 B 6H 4 28 30 47.78 0.941 0.949 16.9 745 B 6H 4 38 40 47.88 0.943 0.951 15.3 745 B 6H 4 48 50 47.98 0.945 0.953 9.1 745 B 6H 4 58 60 48.08 0.947 0.955 22.0 745 B 6H 4 68 70 48.18 0.949 0.957 25.8 745 B 6H 4 78 80 48.28 0.951 0.959 17.9 745 B 6H 4 88 90 48.38 0.953 0.960 14.9 745 B 6H 4 98 100 48.48 0.955 0.962 18.6 745 B 6H 4 108 110 48.58 0.957 0.964 15.2 745 B 6H 4 118 120 48.68 0.959 0.966 17.1 745 B 6H 5 8 10 49.08 0.968 0.973 19.9 745 B 6H 5 18 20 49.18 0.970 0.975 20.1 745 B 6H 5 28 30 49.28 0.972 0.977 34.9 745 B 6H 5 38 40 49.38 0.974 0.979 34.3 745 B 6H 5 48 50 49.48 0.976 0.981 32.3 745 B 6H 5 58 60 49.58 0.978 0.983 22.9 745 B 6H 5 68 70 49.68 0.980 0.985 25.1 745 B 6H 5 78 80 49.78 0.982 0.987 24.6 745 B 6H 5 88 90 49.88 0.984 0.989 21.3 745 B 6H 5 98 100 49.98 0.986 0.991 26.9 745 B 6H 5 108 110 50.08 0.988 0.994 33.7 745 B 6H 5 118 120 50.18 0.990 0.996 31.1 745 B 6H 5 128 130 50.28 0.992 0.999 34.8 745 B 6H 5 138 140 50.38 0.994 1.002 29.0 745 B 6H 5 148 150 50.48 0.996 1.005 23.1 745 B 6H 6 8 10 50.58 0.998 1.009 23.7 745 B 6H 6 18 20 50.68 1.000 1.012 31.6 745 B 6H 6 28 30 50.78 1.002 1.015 32.2 745 B 6H 6 38 40 50.88 1.004 1.018 30.0 745 B 6H 6 48 50 50.98 1.006 1.021 42.5 745 B 6H 6 58 60 51.08 1.008 1.025 40.3 745 B 6H 6 68 70 51.18 1.010 1.030 34.8 745 B 6H 6 78 80 51.28 1.012 1.034 23.9 745 B 6H 6 88 90 51.38 1.014 1.038 16.2 745 B 6H 6 98 100 51.48 1.016 1.039 15.6 745 B 6H 6 108 110 51.58 1.018 1.041 22.0 745 B 6H 6 118 120 51.68 1.020 1.042 22.2 745 B 6H 6 128 130 51.78 1.022 1.044 25.7 745 B 6H 6 138 140 51.88 1.025 1.045 26.7 745 B 6H 6 148 150 51.98 1.027 1.047 30.0 745 B 6H 7 8 10 52.08 1.029 1.048 29.3 745 B 7H 1 8 10 52.58 1.039 1.055 31.2 745 B 7H 1 18 20 52.68 1.041 1.056 26.6 745 B 7H 1 28 30 52.78 1.043 1.058 29.7 745 B 7H 1 38 40 52.88 1.045 1.059 31.6 745 B 7H 1 48 50 52.98 1.047 1.061 31.3 745 B 7H 1 58 60 53.08 1.049 1.062 33.2 745 B 7H 1 68 70 53.18 1.051 1.064 33.8 745 B 7H 1 78 80 53.28 1.053 1.065 31.9 745 B 7H 1 88 90 53.38 1.055 1.066 35.2 745 B 7H 1 98 100 53.48 1.057 1.068 36.5 745 B 7H 1 108 110 53.58 1.059 1.069 36.6 745 B 7H 1 118 120 53.68 1.061 1.071 43.7 745 B 7H 1 128 130 53.78 1.063 1.072 43.9 745 B 7H 1 138 140 53.88 1.065 1.076 43.0 745 B 7H 2 8 10 54.0