Cenozoic High Latitude Paleoceanography: New Perspectives from the Arctic and Subantarctic Pacific by Lindsey M. Waddell A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Oceanography: Marine Geology and Geochemistry) in The University of Michigan 2009 Doctoral Committee: Assistant Professor Ingrid L. Hendy, Chair Professor Mary Anne Carroll Professor Lynn M. Walter Associate Professor Christopher J. Poulsen Table of Contents List of Figures................................................................................................................... iii List of Tables ......................................................................................................................v List of Appendices............................................................................................................ vi Abstract............................................................................................................................ vii Chapter 1. Introduction....................................................................................................................1 2. Ventilation of the Abyssal Southern Ocean During the Late Neogene: A New Perspective from the Subantarctic Pacific ......................................................21 3. Global Overturning Circulation During the Late Neogene: New Insights from Hiatuses in the Subantarctic Pacific ...........................................55 4. Salinity of the Eocene Arctic Ocean from Oxygen Isotope Analysis of Fish Bone Carbonate...............................................................................................73 5. The Isotopic Integrity of Biogenic Apatite Carbonate in Deep Sea Settings........109 6. Conclusions and Future Research............................................................................130 Appendices......................................................................................................................134 ii List of Figures Figure 2.1. Bathymetric map of the study region, depicting the core locations of MV0502-4JC (50°20'S, 148°08'W, 4286 m) and pre-existing Eltanin core ELT 25-11 (50°02'S, 127°31'W, 3969 m), for which new results are presented in this study. ....................................................................................43 Figure 2.2. Map showing the location of existing benthic stable isotope records that are compared to MV0502-4JC in this study. ................................................43 Figure 2.3. Compilation of the results from MV0502-4JC..............................................44 Figure 2.4. Compilation of the results from ELT 25-11. .................................................45 Figure 2.5. Comparison of the benthic δ13C record of the late Miocene carbon shift from MV0502-4JC to that of ODP Site 704 in the South Atlantic...........................46 Figure 2.6. Comparison of the MV0502-4JC (red) benthic δ13C (top) and δ18O (bottom) records of the late Pliocene climate transition to records from ODP Sites 849 (black, Pacific Ocean), 607 (green, North Atlantic), and 704/1090 (blue, South Atlantic).................................................................................47 Figure 3.1. Bathymetric map of the study region, depicting the core locations of MV0502 4JC (50°20'S, 148°08'W, 4286 m) and Eltanin cores, ELT 25-11 (50°02'S, 127°31'W, 3969 m) and ELT 20-2 (49°00'S, 144°50'W, 4517 m). ..................67 Figure 3.2. Temperature of water at 4 km water depth relative to the core locations discussed in this chapter. ...................................................................................67 Figure 3.3. Benthic stable isotope (Cibicidoides spp.) and weight percent CaCO3 results from MV0502-4JC. ..................................................................................68 Figure 4.1. Paleoreconstruction of the Arctic Region at 50 Ma showing the location of the Arctic Coring Expedition (ACEX) 302 Sites examined in this study.......................................................................................................................98 Figure 4.2. Secondary electron images of fish bone taken from Sample 11X 2W 46-48...................................................................................................................99 Figure 4.3. Results of a linear regression performed on the zero-salinity 18 Intercepts and slopes of the δ Ow-salinity equations listed in Table 4.2 for the North Atlantic and Arctic. ..................................................................................100 iii Figure 4.4 (a, b) Oxygen and carbon isotopic composition of fish debris from IODP Expedition 302, Holes M0002A and M0004A. (c) Temperatures used in calculating Arctic salinity. (d) Calculated salinity range based on δ18O data in (a) and temperatures shown in (c). .............................................................101 Figure 5.1. Comparison of the δ18O (left) and δ13C (right) values of benthic foramininifera, planktonic foraminifera, and fish debris obtained in this study with the results of Dutton et al. (2005) from ODP Site 1209 on the Shatsky Rise.........................................................................................................123 Figure 5.2. Comparison of the δ18O (top) and δ13C (bottom) values of fish debris and benthic foraminifera from the late Miocene portion of subantarctic Pacific core MV0502-4JC...............................................................................................124 Figure 5.3. Plot showing the stable isotope values of fish apatite carbonate from all of the locations listed in Table 1. ......................................................................125 iv List of Tables Table 2.1. Location and Water Depth of Late Neogene Stable Isotope Records Discussed in This Study......................................................................................41 Table 2.2. Important Age Datums Identified in MV0502-4JC. .......................................41 Table 2.3. Important Age Datums Identified in ELT 25-11.............................................42 Table 4.1. Chemical Treatment Test Performed on Sample M0002A-55X-CC .............................................................................................................95 Table 4.2. δ18Ow-Salinity Relation for Sites in the Arctic and North Atlantic Obtained from Surface Water Measurements Across Diverse Modern Salinity Gradients..............................................................................................................95 Table 4.3. Stable Isotope Data Generated from the Analysis of Fish Bones in ACEX Holes 302 M0002A and M0004A and the Calculated Salinity Range for Each Sample................................................................................................................ 96 Table 4.4. Estimates of Arctic Salinity Based on Different Assumptions of 18 18 18 Δδ Ow/ΔS, δ O of Precipitation (δ Op), and Temperature for the PETM, the Azolla Event, 47.6 Ma (A Possible Low Salinity Event), 46.3 Ma (A Possible High Salinity Event), Average Eocene Conditions, and Miocene Sample 44X-CC. ...............................................................................................97 Table 4.5. Comparison Between Stable Isotope Values Obtained from Early Eocene Untreated Fish Bone and Teeth from ODP Hole 913B in the Norwegian- Greenland Sea and Full-Marine DSDP Hole 550 in the Northeastern Atlantic by Andreasson et al. [1997] versus This Study.......................................................................97 Table 5.1. Location of core sites discussed in this study. ..............................................120 Table 5.2. Oxygen and carbon isotopic composition of Eocene fish apatite and foraminifera from ODP Leg 198, Sites 1209 and 1212, Shatsky Rise. ...................120 Table 5.3. Oxygen and carbon isotopic composition of Miocene fish apatite and foraminifera from MV0502-4JC, Subantarctic Pacific............................................121 Table 5.4. Oxygen and carbon isotopic composition of fish apatite and foraminifera from the Røsnæs Clay Formation (from Andreasson et al., 1996; Schmitz et al., 1996). ......................................................................................................121 Table 5.5. Oxygen and carbon isotopic composition of fish apatite and foraminifera from DSDP Hole 550 (from Andreasson et al., 1996; Charisi and Schmitz, 1996).............................................................................................122 v List of Appendices Appendix A. Stable Isotope and Compositional Data from MV0502-4JC....................134 Appendix B: Radiolarian biostratigraphy for MV0502-4JC .........................................141 Appendix C: Weight Percent CaCO3 from MV0502-4JC.............................................142 Appendix D. Stable Isotope and Compositional Data from ELT 25-11........................143 Appendix E: Radiolarian biostratigraphy for ELT 25-11..............................................145 Appendix F: Weight Percent CaCO3 from ELT 25-11 and ELT 20-2 ..........................146 Appendix G. Stable Isotope Data from ELT 25-11.......................................................147 Appendix H. Radiolarian biostratigraphy from ELT 20-2 ............................................148 Appendix I. Laboratory Procedure for the Preparation of Fish Debris for Oxygen and Carbon Stable Isotope Analysis............................................................149