Falkland Plateau DSDP511 Cretaceous Foraminiferal Stable Isotope Data ----------------------------------------------------------------------- World Data Center for Paleoclimatology, Boulder and NOAA Paleoclimatology Program ----------------------------------------------------------------------- NOTE: PLEASE CITE CONTRIBUTORS WHEN USING THIS DATA!!!!! NAME OF DATA SET: Falkland Plateau DSDP511 Cretaceous Foraminiferal Stable Isotope Data LAST UPDATE: 7/2006 (Original receipt by WDC Paleo) CONTRIBUTOR: Karen Bice, Woods Hole Oceanographic Institution IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2006-071 SUGGESTED DATA CITATION: Bice, K.L., et al. 2006. Falkland Plateau DSDP511 Cretaceous Foraminiferal Stable Isotope Data. IGBP PAGES/World Data Center for Paleoclimatology Data Contribution Series # 2006-071. NOAA/NCDC Paleoclimatology Program, Boulder CO, USA. ORIGINAL REFERENCE: Bice, K.L., B.T. Huber, and R.D. Norris. 2003. Extreme polar warmth during the Cretaceous greenhouse? Paradox of the Late Turonian d18O record at Deep Sea Drilling Project Site 511. Paleoceanography, vol. 18, No. 2, 1031, doi: 10.1029/2002PA000848. ABSTRACT: Oxygen isotope data for upper Turonian planktonic foraminifera at Deep Sea Drilling Project Site 511 (Falkland Plateau, 60°S paleolatitude) exhibit an ~2 per mil excursion to values as low as -4.66 per mil (Vienna Peedee belemnite standard; PDB) coincident with the warmest tropical temperature estimates yet obtained for the open ocean. The lowest planktonic foraminifer d18O values suggest that the upper ocean was as warm as 30–32°C. This is an extraordinary temperature for 60°S latitude but is consistent with temperatures estimated from apparently coeval mollusc d18O from nearby James Ross Island (65°S paleolatitude). Glassy textural preservation, a well-defined depth distribution in Site 511 planktonics, low sediment burial temperature (~32°C), and lack of evidence of highly depleted pore waters argue against diagenesis (even solid state diffusion) as the cause of the very depleted planktonic values. The lack of change in benthic foraminifer d18O suggests brackish water capping as the mechanism for the low planktonic d18O values. However, mixing ratio calculations show that the amount of freshwater required to produce a 2 per mil shift in ambient water would drive a 7 psu decrease in salinity. The abundance and diversity of planktonic foraminifera and nannofossils, high planktonic:benthic ratios, and the appearance of keeled foraminifera argue against lower-than-normal marine salinities. Isotope calculations and climate models indicate that we cannot call upon more depleted freshwater d18O to explain this record. Without more late Turonian data, especially from outside the South Atlantic basin, we can currently only speculate on possible causes of this paradoxical record from the core of the Cretaceous greenhouse. GEOGRAPHIC REGION: Falkland Plateau, western South Atlantic Ocean PERIOD OF RECORD: Upper Turonian, Cretaceous, ~90 Million Yr BP. FUNDING SOURCES: National Science Foundation (USA) ATM-0000545 and EAR-9909658, Smithsonian Walcott Fund, Smithsonian Scholarly Studies Fund, Andrew W. Mellon Foundation Endowed Fund for Innovative Research. DESCRIPTION: Carbon and oxygen stable isotope ratios for Cretaceous planktonic and benthic foraminifera, DSDP Site 511, present location: 51°00.28’S, 46°58.30’W These data expand the isotope record published by Huber et al. (1995, GSA Bull., v. 107, p. 1164-1191). The temporal resolution of the data is on the order of 10^5 years. DATA: Column 1: Core-section Column 2: Interval (cm) Column 3: Depth MBSF Column 4: Taxon Column 5: d13C (per mil PDB) Column 6: d180 (per mil PDB) Sect. Interval MBSF Taxon d13C d18O 47-1 106-108 405.06 Hedbergella sp. 0.746 -1.721 47-2 106-108 406.56 Hedbergella sp. -0.048 -1.768 47-2 106-108 406.56 Heterohelix moremani -0.483 -2.467 47-2 120-122 406.7 Hedbergella sp. 1.826 -2.169 47-2 120-122 406.7 mixed benthics 0.176 -1.222 47-3 34-36 407.34 Heterohelix moremani 0.758 -3.106 47-3 34-36 407.34 Whiteinella baltica 1.453 -2.485 47-3 34-36 407.34 mixed benthics 0.457 -1.459 47-3 105-107 408.05 Globigerinelloides volutus 1.592 -2.224 47-3 105-107 408.05 Hedbergella sp. 1.294 -2.205 47-3 105-107 408.05 Whiteinella baltica 1.586 -2.763 47-3 105-107 408.05 Heterohelix moremani 1.312 -2.945 47-4 30-32 408.8 Whiteinella baltica 2.104 -3.578 47-4 106-108 409.56 Globigerinelloides volutus 1.276 -2.816 47-4 106-108 409.56 Hedbergella sp. 1.296 -2.906 47-4 106-108 409.56 Whiteinella baltica 1.528 -3.073 47-4 106-108 409.56 Heterohelix moremani 1.161 -3.862 47-4 106-108 409.56 Archaeoglobigerina bosquensis 1.757 -3.374 47-4 106-108 409.56 mixed benthics -0.904 -1.682 47-5 13.5-15.5 410.14 Whiteinella baltica 1.706 -4.078 47-5 13.5-15.5 410.14 Marginotruncana marginata 0.849 -3.98 47-5 13.5-15.5 410.14 Gyroidinoides globosus -0.256 -1.477 47-5 33-36 410.33 Globigerinelloides volutus 1.499 -3.031 47-5 33-36 410.33 Hedbergella sp. 1.632 -3.12 47-5 33-36 410.33 Whiteinella baltica 1.762 -3.466 47-5 33-36 410.33 Heterohelix moremani 1.062 -3.802 47-5 33-36 410.33 Archaeoglobigerina bosquensis 1.737 -3.921 47-5 33-36 410.33 Marginotruncana marginata 1.219 -4.115 47-5 33-36 410.33 Gyroidinoides globosus -0.655 -1.932 47-5 33-36 410.33 mixed benthics -0.533 -1.675 47-5 72-74 410.72 Whiteinella baltica 1.779 -4.014 47-5 72-74 410.72 Archaeoglobigerina bosquensis 1.627 -3.876 47-5 72-74 410.72 Marginotruncana marginata 1.221 -4.154 47-5 72-74 410.72 Gyroidinoides globosus -0.338 -1.653 47-5 109-111 411.09 Globigerinelloides volutus 1.218 -2.938 47-5 109-111 411.09 Hedbergella sp. 1.369 -3.164 47-5 109-111 411.09 Whiteinella baltica 1.93 -4.085 47-5 109-111 411.09 Heterohelix moremani 0.995 -4.164 47-5 109-111 411.09 Archaeoglobigerina bosquensis 1.707 -4.334 47-5 109-111 411.09 Marginotruncana marginata 0.941 -3.61 47-5 124-126 411.24 Whiteinella baltica 1.635 -4.473 47-5 124-126 411.24 Archaeoglobigerina bosquensis 1.429 -4.089 47-5 124-126 411.24 Berthelina sp. 0.598 -1.585 47-5 124-126 411.24 mixed benthics -0.92 -1.476 47-6 18-20 411.68 Marginotruncana marginata 1.673 -4.664 47-6 18-20 411.68 Dentalina sp. -0.789 -1.753 47-6 18-20 411.68 shallow infaunal benthics -0.318 -1.612 47-6 31-33 411.81 Globigerinelloides volutus 1.522 -2.369 47-6 31-33 411.81 Hedbergella sp. 1.764 -2.908 47-6 31-33 411.81 Whiteinella baltica 2.061 -3.677 47-6 31-33 411.81 Heterohelix moremani 1.107 -3.277 47-6 31-33 411.81 Archaeoglobigerina bosquensis 2.081 -3.589 47-6 31-33 411.81 Marginotruncana marginata 1.69 -4.24 47-6 31-33 411.81 Marginotruncana marginata 1.849 -4.191 47-6 38-40 411.88 mixed benthics -0.111 -1.542 47-6 64.5-66.5 412.14 Whiteinella baltica 1.647 -4.282 47-6 64.5-66.5 412.14 Marginotruncana marginata 1.172 -3.584 47-6 64.5-66.5 412.14 Dentalina sp. -1.807 -2.246 47-6 72-74 412.22 Hedbergella sp. 0.835 -2.348 47-6 72-74 412.22 Praeglobotruncana delrioensis -0.006 -2.236 47-6 72-74 412.22 trocospiral benthics -0.206 -1.664 47-6 72-74 412.22 deeper infaunal benthics -1.129 -1.83 47-6 98-100 412.48 Praeglobotruncana stephani 0.275 -2.39 47-6 98-100 412.48 Berthelina sp. 0.613 -1.334 47-6 107.5-109.5 412.58 shallow infaunal benthics 0.4 -1.742 47-6 105-107 412.55 Globigerinelloides volutus 1.501 -2.146 47-6 105-107 412.55 Hedbergella sp. 1.358 -2.244 47-6 126-128 412.76 Berthelina sp. 0.333 -1.381 48-1 24-27 413.74 Berthelina sp. 0.631 -1.475 48-1 33-35 413.83 Whiteinella baltica 1.154 -2.327 48-1 33-35 413.83 Whiteinella baltica 1.238 -2.371 48-1 33-35 413.83 Hedbergella sp. planispira 1.324 -2.194 48-1 33-35 413.83 Praeglobotruncana stephani 0.339 -2.075 48-1 33-35 413.83 Praeglobotruncana stephani 0.295 -2.028 48-1 33-35 413.83 mixed benthics -0.087 -1.582 48-1 33-35 413.83 deeper infaunal benthics 0.013 -1.542 49-5 65.5-67.5 429.36 Hedbergella sp. planispira 1.511 -0.811 49-5 65.5-67.5 429.36 Hedbergella sp. portsdownensis 1.37 -1.476 49-5 65.5-67.5 429.36 Berthelina sp. 1.086 -0.558 49-5 65.5-67.5 429.36 Berthelina sp. 1.376 -0.448 49-5 103-105 430.04 Hedbergella yezoana 2.784 -1.457 49-5 103-105 430.04 Berthelina sp. 1.704 -0.555