International Ocean Discovery Program Expedition 371 Preliminary Report Tasman Frontier Subduction Initiation and Paleogene Climate 27 July–26 September 2017 Rupert Sutherland, Gerald R. Dickens, Peter Blum, and the Expedition 371 Scientists Publisher’s notes Core samples and the wider set of data from the science program covered in this report are under moratorium and accessible only to Science Party members until 2 February 2019. This publication was prepared by the JOIDES Resolution Science Operator (JRSO) at Texas A&M University (TAMU) as an account of work performed under the International Ocean Discovery Program (IODP). Funding for IODP is provided by the following international partners: National Science Foundation (NSF), United States Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan European Consortium for Ocean Research Drilling (ECORD) Ministry of Science and Technology (MOST), People’s Republic of China Korea Institute of Geoscience and Mineral Resources (KIGAM) Australia-New Zealand IODP Consortium (ANZIC) Ministry of Earth Sciences (MoES), India Coordination for Improvement of Higher Education Personnel (CAPES), Brazil Portions of this work may have been published in whole or in part in other IODP documents or publications. Disclaimer Any opinions, findings, and conclusions or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the views of the participating agencies, TAMU, or Texas A&M Research Foundation. Copyright Except where otherwise noted, this work is licensed under the Creative Commons Attribution 4.0 International (CC BY 4.0) license (https://creativecommons.org/ licenses/by/4.0/). Unrestricted use, distribution, and reproduction are permitted, provided the original author and source are credited. Citation Sutherland, R., Dickens, G.R., Blum, P., and the Expedition 371 Scientists, 2018. Expedition 371 Preliminary Report: Tasman Frontier Subduction Initiation and Paleogene Climate. International Ocean Discovery Program. https://doi.org/10.14379/iodp.pr.371.2018 ISSN World Wide Web: 2372-9562 January 2018 R. Sutherland et al. Expedition 371 Preliminary Report Expedition 371 participants Expedition 371 scientists Rupert Sutherland Margot J. Cramwinckel Co-Chief Scientist Organic Geochemist/Palynologist Department of Geography, Environment, Earth Sciences Department of Earth Sciences Victoria University of Wellington Utrecht University New Zealand The Netherlands [email protected] [email protected] Gerald R. Dickens Edoardo Dallanave Co-Chief Scientist Paleomagnetist Department of Earth, Environmental and Planetary Sciences Department of Earth and Environmental Sciences, Geophysics Rice University Section USA Ludwig-Maximilians-Universität München [email protected] Germany [email protected] Peter Blum Expedition Project Manager/Staff Scientist Michelle K. Drake International Ocean Discovery Program Sedimentologist Texas A&M University Ocean Sciences Department USA University of California, Santa Cruz [email protected] USA [email protected] Claudia Agnini Paleontologist (nannofossils) Samuel J.G. Etienne Dipartimento di Geoscienze Sedimentologist Università degli Studi di Padova Department of Industry, Mines and Energy of New Caledonia Italy Geological Survey of New Caledonia [email protected] New Caledonia [email protected] Laia Alegret Paleontologist (foraminifers) Martino Giorgioni Departamento de Ciencias de la Tierra (Paleontología) Sedimentologist Universidad de Zaragoza Instituto de Geociência Spain Universidade de Brasília [email protected] Brazil [email protected] Joyeeta Bhattacharya Sedimentologist Michael Gurnis Department of Earth, Environmental and Planetary Sciences Physical Properties Specialist Rice University Seismological Laboratory USA California Institute of Technology [email protected] USA [email protected] Aurelien Bordenave Sedimentologist Dustin T. Harper Geological Survey of New Caledonia Stratigraphic Correlator New Caledonia Department of Earth and Planetary Sciences [email protected] University of California, Santa Cruz USA Liao Chang [email protected] Paleomagnetist School of Earth and Space Sciences Huai-Hsuan May Huang Peking University Paleontologist (ostracods) China Atmosphere and Ocean Research Institute [email protected] The University of Tokyo Japan Julien Collot [email protected] Physical Properties Specialist Geological Survey of New Caledonia New Caledonia [email protected] 3 R. Sutherland et al. Expedition 371 Preliminary Report Allison L. Keller Stephen F. Pekar Sedimentologist Sedimentologist Department of Earth Sciences School of Earth and Environmental Sciences University of California, Riverside Queens College (CUNY) USA USA [email protected] [email protected] Adriane R. Lam Donald E. Penman Paleontologist (foraminifers) Sedimentologist Department of Geosciences Department of Geology and Geophysics University of Massachusetts Yale University USA USA [email protected] [email protected] He Li Saneatsu Saito Inorganic Geochemist Physical Properties Specialist Institute of Oceanology, Chinese Academy of Sciences Research and Development Center for Ocean Drilling Science China Japan Agency for Marine-Earth Science and Technology [email protected] Japan [email protected] Hiroki Matsui Paleontologist (foraminifers) Wanda R. Stratford Department of Earth Science Physical Properties Specialist Tohoku University Marine Geosciences Japan GNS Science [email protected] New Zealand [email protected] Cherry Newsam Paleontologist (nannofossils) Thomas Westerhold Department of Earth Sciences Stratigraphic Correlator University College London Center for Marine Environmental Sciences (MARUM) United Kingdom University of Bremen [email protected] Germany [email protected] Yu-Hyeon Park Organic Geochemist Xiaoli Zhou Department of Oceanography Inorganic Geochemist Pusan National University Institute of Marine and Coastal Sciences Republic of Korea Rutgers, The State University of New Jersey [email protected] USA [email protected] Kristina M. Pascher Paleontologist (radiolarians) GNS Science New Zealand [email protected] Observers Gayane Asatryan Hugh E.G. Morgans Observer/Paleontologist (radiolarians) Observer/Paleontologist (foraminifers) School of Earth and Environmental Sciences Paleontology and Environmental Change Section University of Queensland GNS Science Australia New Zealand [email protected] [email protected] Education and outreach Debra E. Beamish Adam J. Kurtz Education/Outreach Officer Education/Outreach Officer Australia USA [email protected] [email protected] 4 R. Sutherland et al. Expedition 371 Preliminary Report Operational and technical staff Siem Offshore AS officials Steve Bradley Mark Robinson Master of the Drilling Vessel Offshore Installation Manager Jake Robinson Master of the Drilling Vessel JRSO shipboard personnel and technical representatives Timothy Blaisdell Randy Gjesvold Applications Developer Marine Instrumentation Specialist Susan Boehm Michael Hodge Thin Section Laboratory Marine Computer Specialist Inva Braha Minh Huynh Marine Laboratory Specialist (temporary) Marine Computer Specialist Lisa Brandt Nicolette Lawler Chemistry Laboratory X-Ray Laboratory Chad Broyles Daniel Marone Curatorial Specialist Marine Laboratory Specialist (temporary) Lisa Crowder Aaron Mechler Assistant Laboratory Officer Chemistry Laboratory Douglas Cummings Mike Meiring Publications Specialist Electronics Specialist Aaron de Loach Stephen Midgley Core Laboratory Operations Superintendent Keith Dupuis William Mills Underway Geophysics Laboratory Laboratory Officer Sheryl Frazier Beth Novak Physical Properties Laboratory Paleomagnetism Laboratory Timothy Fulton Garrick Van Rensburg Imaging Specialist Marine Instrumentation Specialist Luke Furfey Rui Wang Marine Laboratory Specialist (temporary) Applications Developer Clayton Furman Logging Engineer (Schlumberger) 5 R. Sutherland et al. Expedition 371 Preliminary Report Abstract Eocene tectonic change occurred at a turning point in Cenozoic climate. Long-term global warming through the Paleocene–Eocene International Ocean Discovery Program (IODP) Expedition 371 transition culminated in the Early Eocene Climate Optimum drilled six sites in the Tasman Sea of the southwest Pacific between (EECO; ~53–49 Ma), which was followed by overall cooling 27 July and 26 September 2017. The primary goal was to understand through the remainder of the Cenozoic (Figure F5) (Zachos et al., Tonga-Kermadec subduction initiation through recovery of Paleo- 2008). A secondary scientific goal of Expedition 371 was to address gene sediment records. Secondary goals involved understanding re- the question of why Earth’s climate might move between multimil- gional oceanography and climate since the Paleogene. Six sites were lion-year greenhouse and icehouse climate states. Under very high drilled, recovering 2506 m of cored sediment and volcanic rock in pCO2 conditions or high climate sensitivity, global climate models 36.4 days of on-site drilling during a total expedition length of 58 (Huber and Caballero, 2011; Lunt et al., 2012) can reasonably simu- days. Wireline logs were collected at two sites. Shipboard observa- late early Eocene warming in many regions (Douglas et al., 2014; tions made using cores and logs represent a substantial gain in fun- Tripati et al., 2003) but not the extreme warmth previously reported damental knowledge about northern