# Gulf of Aden DSDP Site 231 Pliocene to late Pleistocene Biomarker Data #----------------------------------------------------------------------- # World Data Service for Paleoclimatology, Boulder # and # NOAA Paleoclimatology Program # National Centers for Environmental Information (NCEI) #----------------------------------------------------------------------- # # NOTE: Please cite Publication, and Online_Resource and date accessed when using these data. # If there is no publication information, please cite Investigators, Title, and Online_Resource and date accessed. # # Online_Resource: https://www.ncdc.noaa.gov/paleo/study/20145 # Online_Resource: http://www1.ncdc.noaa.gov/pub/data/paleo/contributions_by_author/liddy2016/liddy2016d2h.txt # # Original_Source_URL: # # Description/Documentation lines begin with # # Data lines have no # # # Archive: Paleoceanography # # Parameter_Keywords: biomarkers, carbon isotopes #-------------------- # Contribution_Date # Date: 2016-08-23 #-------------------- # Title # Study_Name: Gulf of Aden DSDP Site 231 Pliocene to late Pleistocene Biomarker Data #-------------------- # Investigators # Investigators: Liddy, H.M.; Feakins, S.J.; Tierney, J.E. #-------------------- # Description_and_Notes # Description: Plio-Pleistocene records of leaf wax carbon and hydrogen isotopes from a marine sediment core from the Gulf of Aden # are used to assess changes in vegetation and aridity across the Horn of Africa. During the same interval, Gulf of Aden TEX86 values # reflects subsurface ocean temperatures, and BIT index values are used to assess the GDGT contribution from soils. #-------------------- # Publication # Authors: Hannah M. Liddy, Sarah J. Feakins, Jessica E. Tierney # Published_Date_or_Year: 2016-09-01 # Published_Title: Cooling and drying in northeast Africa across the Pliocene # Journal_Name: Earth and Planetary Science Letters # Volume: 449 # Edition: # Issue: # Pages: 430-438 # Report_Number: # DOI: 10.1016/j.epsl.2016.05.005 # Online_Resource: http://www.sciencedirect.com/science/article/pii/S0012821X1630214X # Full_Citation: # Abstract: Terrestrial records suggest that Northeast Africa experienced drying during the Pliocene; however, these records are often incomplete in time and space, and questions about this shift in climate remain. Here, we use marine sediments from Deep Sea Drilling Project (DSDP) Site 231 in the Gulf of Aden to generate a multi-proxy organic geochemical record of northeast African climate spanning 5.3-2 Ma. This new record provides a regional perspective on climate and serves as context for the fossil record of early hominin evolution. We measured leaf wax carbon (d13Cwax) and hydrogen (dDwax) isotopic composition and TEX86 (tetraether index of 86 carbons) to investigate past changes in vegetation, aridity, and ocean temperature, respectively. In the earliest Pliocene, we infer warm subsurface ocean temperatures from TEX86, semi-arid conditions on land and extensive C4 grasslands based on dDwax, d13Cwax and previously published pollen. After 5 Ma, ocean temperatures gradually cooled, and at 4.3 Ma there was a transition to arid conditions on land based on dDwax and pollen. Grasslands yielded to a mid Pliocene landscape of dry shrublands. This drying appears to be an atmospheric response to cooling ocean temperatures, which may reflect changes in tropical ocean circulation, the intensification of Indian Monsoon winds or perhaps other changes associated with Pliocene cooling. #------------------ # Funding_Agency # Funding_Agency_Name: International Ocean Discovery Program # Grant: Schlanger Ocean Drilling Fellowship #------------------ # Funding_Agency # Funding_Agency_Name: US National Science Foundation # Grant: OCE-1203892 #------------------ # Funding_Agency # Funding_Agency_Name: University of Southern California # Grant: Women in Science and Engineering Program #------------------ # Site_Information # Site_Name: DSDP231 # Location: Ocean>Indian Ocean>Arabian Sea # Country: # Northernmost_Latitude: 11.89 # Southernmost_Latitude: 11.89 # Easternmost_Longitude: 48.25 # Westernmost_Longitude: 48.25 # Elevation: -2152 m #------------------ # Data_Collection # Collection_Name: Liddy2016d2H # Earliest_Year: 5239000 # Most_Recent_Year: 2159000 # Time_Unit: Cal. Year BP # Core_Length: m # Notes: #------------------ # Chronology_Information # Chronology: # Age (in millions of years before present) using a tephrostratigraphic and nannofossil age model (Feakins et al., 2013) #---------------- # Variables # # Data variables follow are preceded by "##" in columns one and two. # Data line variables format: Variables list, one per line, shortname-tab-longname-tab-longname components (9 components: what, material, error, units, seasonality, archive, detail, method, C or N for Character or Numeric data) # ## depth_m depth, , , m, , , , ,N ## age_calmyBP age, , , millions of calendar years before present, , , , ,N ## d2HleafwaxC28 delta2H, C28 n-alkanoic acids, , per mil VSMOW, , , , ,N ## d2HleafwaxC28std delta2H standard deviation, leaf wax C-28 acids error, , per mil, , , standard deviation of replicates, ,N # #---------------- # Data: # Data lines follow (have no #) # Data line format - tab-delimited text, variable short name as header # Missing Values: n.d. # Table 2: Plant wax hydrogen Isotope data from DSDP Site 231 # depth_m age_calmyBP d2HleafwaxC28 d2HleafwaxC28std 105.15 2.159 -130.8 0.2 105.60 2.168 -136.1 5.8 105.75 2.171 -140.8 3.8 110.40 2.265 -131.3 0.4 112.35 2.304 -126.5 0.9 115.25 2.362 -133.3 0.2 122.50 2.520 -131.1 n.d. 124.30 2.561 -130.0 0.9 131.85 2.735 -129.6 n.d. 133.20 2.766 -125.2 2.6 134.40 2.793 -124.2 1.2 135.00 2.807 -128.7 0.3 135.60 2.821 -126.9 0.6 136.20 2.835 -132.9 4.7 136.80 2.848 -131.5 0.7 137.40 2.862 -130.3 2.5 138.00 2.876 -135.3 0.9 138.60 2.890 -135.1 2.7 139.20 2.904 -130.7 n.d. 141.05 2.946 -136.8 1.0 143.30 2.998 -125.3 5.5 144.80 3.032 -130.0 3.9 144.95 3.036 -137.8 n.d. 145.40 3.046 -141.9 1.9 146.60 3.074 -132.9 1.8 147.20 3.087 -136.0 n.d. 150.10 3.154 -129.1 n.d. 150.70 3.168 -135.9 0.1 151.30 3.182 -130.6 1.7 151.90 3.195 -131.4 0.0 152.35 3.206 -131.7 1.2 160.50 3.393 -144.0 4.8 160.95 3.403 -137.4 n.d. 162.02 3.428 -148.5 5.7 162.17 3.431 -129.0 n.d. 163.35 3.458 -133.2 0.9 169.85 3.591 -141.1 1.6 171.50 3.630 -139.1 1.3 171.80 3.643 -138.5 0.4 173.15 3.673 -134.1 0.1 173.90 3.687 -127.7 0.7 174.65 3.702 -137.4 1.4 176.45 3.737 -132.3 4.6 176.90 3.746 -127.8 0.8 177.35 3.754 -142.9 1.7 184.40 3.865 -138.8 6.4 185.60 3.882 -131.8 5.0 188.00 3.915 -142.1 0.1 190.30 3.960 -146.5 1.5 192.00 3.995 -134.2 0.7 192.50 4.005 -130.3 0.3 193.50 4.025 -128.7 2.7 193.90 4.033 -136.8 2.5 194.60 4.048 -129.7 9.5 198.30 4.123 -144.8 1.8 201.10 4.181 -145.3 0.0 201.90 4.197 -131.4 2.3 204.60 4.252 -152.3 0.7 205.30 4.266 -135.2 3.1 206.60 4.293 -135.9 1.4 206.80 4.297 -141.4 3.2 207.30 4.307 -133.2 2.8 208.00 4.322 -134.5 0.1 208.70 4.336 -136.1 n.d. 209.40 4.350 -135.4 1.1 210.10 4.364 -128.4 3.3 210.80 4.379 -131.7 n.d. 212.20 4.407 -147.6 0.7 212.90 4.422 -140.0 2.1 213.60 4.436 -131.5 1.7 216.50 4.495 -150.2 0.2 216.80 4.501 -133.4 0.6 217.90 4.524 -126.1 0.3 219.20 4.550 -126.9 1.7 219.90 4.565 -142.9 0.5 220.60 4.579 -134.7 n.d. 220.70 4.581 -121.9 1.6 222.70 4.622 -141.8 1.1 224.20 4.653 -138.7 0.5 224.90 4.667 -151.1 3.5 226.70 4.704 -128.5 4.2 227.40 4.718 -130.9 0.5 228.20 4.734 -134.0 2.5 228.90 4.749 -128.6 3.1 230.90 4.789 -142.0 3.2 231.60 4.804 -145.7 5.9 236.70 4.908 -154.9 1.7 236.90 4.912 -148.4 0.1 238.20 4.939 -152.5 0.3 239.60 4.967 -158.2 1.3 240.30 4.982 -147.5 0.8 241.70 5.010 -164.0 6.6 242.40 5.024 -141.7 1.4 243.10 5.039 -139.9 0.5 244.50 5.067 -131.8 0.1 245.20 5.082 -164.7 3.6 246.60 5.110 -161.3 n.d. 247.30 5.125 -144.6 2.2 248.00 5.139 -155.1 1.7 249.40 5.168 -140.0 1.6 250.10 5.182 -155.3 0.5 250.80 5.196 -131.9 0.4 251.20 5.204 -142.6 2.6 252.80 5.237 -139.3 n.d. 252.90 5.239 -155.7 1.1