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International Standard Book Number-13: 978-0-309-71338-2
International Standard Book Number-10: 0-309-71338-2
Digital Object Identifier: https://doi.org/10.17226/27414
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2024. Progress and Priorities in Ocean Drilling: In Search of Earth’s Past and Present. Washington, DC: The National Academies Press. https://doi.org/10.17226/27414.

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2025–2035 DECADAL SURVEY OF OCEAN SCIENCES FOR THE NATIONAL SCIENCE FOUNDATION

TUBA OZKAN-HALLER, Co-Chair, Oregon State University

JAMES (JIM) YODER, Co-Chair, Woods Hole Oceanographic Institution (emeritus)

LIHINI ALUWIHARE, Scripps Institution of Oceanography, University of California, San Diego

MONA BEHL, University of Georgia

MARK BEHN, Boston College

BRAD deYOUNG, Canadian Integrated Ocean Observing System

CARLOS GARCIA-QUIJANO, University of Rhode Island

PETER GIRGUIS, Harvard University

LEILA J. HAMDAN, University of Southern Mississippi

MARCIA ISAKSON, Applied Research Laboratories, University of Texas at Austin

JASON LINK, National Oceanic and Atmospheric Administration

ALLISON MILLER, Schmidt Ocean Institute

S. BRADLEY MORAN, University of Alaska Fairbanks

RICHARD W. MURRAY, Woods Hole Oceanographic Institution

STEPHEN R. PALUMBI, Stanford University

ELLA (JOSIE) QUINTRELL, Integrated Ocean Observing System (retired)

YOSHIMI (SHIMI) M. RII, Hawai‘i Institute of Marine Biology, University of Hawai‘i

KRISTEN ST. JOHN, James Madison University

SAMUEL KERSEY STURDIVANT, INSPIRE Environmental

AJIT SUBRAMANIAM, Columbia University

MAYA TOLSTOY, University of Washington College of the Environment

SHANNON VALLEY, Vistant

JAMES ZACHOS, University of California, Santa Cruz

Study Staff

KELLY OSKVIG, Senior Program Officer

LEIGHANN MARTIN, Associate Program Officer (until January 2024)

ZOE ALEXANDER, Senior Program Assistant

ERIK YANISKO, Program Assistant (until January 2024)

Sponsor

NATIONAL SCIENCE FOUNDATION

OCEAN STUDIES BOARD

CLAUDIA BENITEZ-NELSON, Chair, University of South Carolina, Columbia

MARK ABBOTT, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts

ROSIE ‘ANOLANI ALEGADO, University of Hawai‘i, Manoa

CAROL ARNOSTI, University of North Carolina at Chapel Hill

AMY BOWER, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts

LISA CAMPBELL, Duke University, Durham, North Carolina

THOMAS S. CHANCE, ASV Global, LLC (retired), Broussard, Louisiana

DANIEL COSTA, University of California, Santa Cruz

JOHN DELANEY, University of Washington (retired), Seattle

TIMOTHY GALLAUDET, Ocean STL Consulting, LLC, North Beach, Maryland

SCOTT GLENN, Rutgers University, New Brunswick, New Jersey

MARCIA ISAKSON, University of Texas at Austin

LEKELIA JENKINS, Arizona State University, Tempe

NANCY KNOWLTON (NAS), Smithsonian Institution (retired), Washington, DC

ANTHONY MacDONALD, Monmouth University, West Long Branch, New Jersey

GALEN McKINLEY, Columbia University, Palisades, New York

THOMAS MILLER, University of Maryland, Solomons

S. BRADLEY MORAN (ex officio), University of Alaska Fairbanks

RUTH M. PERRY, Shell Exploration & Production Company, Houston, Texas

DEAN ROEMMICH (NAE), Scripps Institution of Oceanography (retired), Solana Beach, California

JAMES SANCHIRICO, University of California, Davis

MARK J. SPALDING, The Ocean Foundation, Washington, DC

PAUL WILLIAMS, Suquamish Tribe, Seattle, Washington

Staff

SUSAN ROBERTS, Director

STACEE KARRAS, Senior Program Officer

KELLY OSKVIG, Senior Program Officer

CAROLINE BELL, Program Officer

LEIGHANN MARTIN, Associate Program Officer (until January 2024)

THANH NGUYEN, Financial Business Partner

DARRYL ACKER-CARTER, Research Associate

SAFAH WYNE, Senior Program Assistant

ZOE ALEXANDER, Senior Program Assistant

ERIK YANISKO, Program Assistant (until January 2024)

Reviewers

This consensus study report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

We thank the following individuals for their review of this report:

ANDREA AHRENS, Stantec

BARBARA BEKINS, U.S. Geological Survey (NAE)

JULIE HUBER, Woods Hole Oceanographic Institution

BO BARKER JORGENSEN, Aarhus University (NAS)

ADRIANE LAM, Binghampton University

WILLIAM MILLER, University of Georgia

MAUREEN RAYMO, Columbia University (NAS)

DAMIAN SAFFER, University of Texas at Austin

JOHN SHERVAIS, Utah State University

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report nor did they see the final draft before its release. The review of this report was overseen by ROBERT DUCE, Texas A&M University, and LARRY MAYER (NAE), University of New Hampshire. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.

Acknowledgments

The committee thanks the following individuals for their contributions during the study process, especially for enriching and informing the discussions at the open session meetings of the committee: James Allen (National Science Foundation [NSF]), Jennifer Biddle (University of Delaware), Donna Blackman (University of California, Santa Cruz), Stefanie Brachfeld (Montclair State University), Carl Brenner (U.S. Science Support Program), Steven D’Hondt (University of Rhode Island), Patrick Fulton (Cornell University), Sean Gulick (University of Texas), David Hodell (University of Cambridge), Celli Hull (Yale University), Minoru Ikehara (Kochi University), Fumio Inagaki (Japanese Agency for Marine-Earth Science and Technology), Kevin Johnson (NSF), Brandi Kiel Reese (University of South Alabama), Anthony Koppers (Oregon State University), Larry Krissek (The Ohio State University), Jessica Labonté (Texas A&M University, Galveston), Adriane Lam (Binghamton University), Chris Lowery (University of Texas), Mitch Malone (Texas A&M University), Kathie Marsaglia (California State University, Northridge), Robert McKay (Victoria University of Wellington), Lisa McNeil (Southampton University), Charna Meth (International Ocean Discovery Program Science Support Office), Heiko Palike (University of Bremen), Becky Robinson (University of Rhode Island), Yair Rosenthal (Rutgers University), Demian Saffer (University of Texas), Daniel Sigman (Princeton University), David Smith (University of Rhode Island), Chijun Sun (National Center for Atmospheric Research), Jason Sylvan (Texas A&M University), Allyson Tessin (Kent State University), Masako Tominaga (Woods Hole Oceanographic Institution), Maureen Walczak (Oregon State University), Allen Walker (NSF’s Technology, Innovation, and Partnership), Shelby Walker (NSF), and Trevor Williams (Texas A&M University). Their input was critical to the completion of the committee’s work.

The committee would also like to thank our primary contact at NSF’s Division of Ocean Sciences, Jim McManus, for his efforts in developing and sponsoring this study and for providing important documents and support upon the committee’s request.

Contents

SUMMARY

1 INTRODUCTION

The Importance of Scientific Ocean Drilling

A Critical Juncture

Preparing for the Next Stage of Scientific Ocean Drilling

Study Origin and Purpose

Study Approach

Report Organization

2 A PRIMER ON SCIENTIFIC OCEAN DRILLING

Terminology and Key Concepts

IODP-2 Management Structure

History of Ocean Drilling

3 HIGH-PRIORITY SCIENCE AREAS: PROGRESS AND FUTURE NEEDS

Evaluating Progress Made Over the Last Decade

Scientific Ocean Drilling Research Priorities

Classification of Scientific Ocean Drilling–Supported Research

Connections to National Priorities and Previous Recommendations to NSF

4 NEEDS FOR ACCOMPLISHING THE SCIENCE PRIORITIES

Realities of Existing and Emerging Drilling Technologies

Opportunities for Using Existing Cores, Boreholes, and Data

Additional Infrastructure Needs

REFERENCES

APPENDIXES

A Committee Statement of Task

B Committee Meeting Agenda and Participant List

C Committee Biographies

Boxes, Figures, and Tables

BOXES

S.1 Interim Report Statement of Task

1.1 Connecting Scientific Ocean Drilling to Other Fields

1.2 2050 Science Framework Flagship Initiatives

1.3 Statement of Task

2.1 Definitions

2.2 Science Supported by a Diverse Workforce

3.1 Advances in Tools and Technologies

3.2 Analytical Chemistry and Proxies of Past Ocean Conditions

3.3 Drilling the Cretaceous–Paleogene Impact Crater and Documenting the Demise and the Recovery of Life

3.4 Sensitivity of Earthquake Detection Using Borehole Observatories

3.5 NanTroSEIZE: A Success Story

3.6 Fulfilling a 60-Year Goal of Scientific Ocean Drilling

3.7 Scientific Ocean Drilling and Ocean CO₂ Removal and Sequestration

FIGURES

S.1 Priorities for future scientific ocean drilling

S.2 Highly sampled core from an interval of high scientific interest

1.1 The long history of scientific ocean drilling

1.2 Schematic circulation of surface currents (solid curves) and deep currents (dashed curves) that form portions of the Atlantic meridional overturing circulation (AMOC)

1.3 A critical juncture in the future of U.S. and international scientific ocean drilling

1.4 The seven strategic objectives of the 2050 Science Framework are broad areas of scientific inquiry that focus on understanding the interconnected Earth system

1.5 Dependencies and relationships of the foundational science mission vessel requirements

2.1 Geological timeline of the last 100 million years, as recorded in scientific ocean drilling records from marine sediments

2.2A The fundamental elements of a piston corer

2.2B Standard piston corer design representing those used in the academic research fleet

2.2C Advanced piston corer design representing those used in scientific ocean drilling

2.3 Seafloor drill rig MARUM-MeBo200, the second-generation MeBo

2.4 Features of new Circulation Obviation Retrofit Kit systems deployed during Expedition 327

2.5 Riserless versus riser drilling technology used in scientific ocean drilling

2.6 Site map of International Ocean Discovery Program expeditions completed in the current phase of the program (2014–2023) and scheduled for the remainder of the program (2023–2024)

2.7 Coauthored networks of scientific ocean drilling–related peer-reviewed journal articles from 2003 to 2021

2.8 Number of U.S. applications and invitations to sail on an IODP-2 expedition, listed by career level, 2015–2023

3.1 Number of completed and planned expeditions during IODP-2, according to themes and challenges from the 2013–2023 IODP Science Plan

3.2 Geographic distribution of completed and planned expeditions during IODP-2 based on themes outlined in the 2013–2023 IODP Science Plan

3.3 Timelines of proxies of temperature and dissolved oxygen (O₂) relative to the phases of scientific ocean drilling

3.4 Priorities for future scientific ocean drilling

3.5 Reconstruction of atmospheric carbon dioxide (CO₂) over the Cenozoic (0–66 million years ago [Ma]) compared with CO₂ scenarios associated with shared socioeconomic pathways (SSPs) SSP2-4.5, SSP4-6.0, and SSP5-8.5

3.6a Map of sites cored in the Ross Sea during Expedition 374

3.6b Photo of core containing Miocene clast-rich sandy diamictite taken from Site 1521 (Unit VII 63R-CC, 4–14 cm)

3.7 Feedback and toolsets for estimating climate sensitivity

3.8 Peak global mean temperature relative to preindustrial, atmospheric CO₂ (preindustrial = 280 ppm, 2014 = 397 ppm, 2023 = 420 ppm), maximum global mean sea level (GMSL, with present day = 0 m) and source(s) of meltwater from Greenland and Antarctica

3.9 Comparison of present, past, and future ocean ecosystem states

3.10 (Left) Pink granite brought up from 10 km below the surface when the asteroid hit the Yucatan Peninsula and continental shelf waters. (Right) Paleontological evidence of the recovery of planktic life at the impact site during the earliest Paleogene

3.11 Illustrations of planktic foraminiferal distribution and species diversity across the Cenozoic (last 66 million years)

3.12 Schematic comparison of past conditions that resulted in ocean anoxic events (left), and modern-day environmental perturbations (right)

3.13 Schematic diagram illustrating the types of geodetic sensors that can be used to distinguish between different slip behaviors on the subduction interface

3.14A Contours show coseismic slip from the 1944 M7.9 earthquake

3.14B Models showing the amount of slip that is resolvable by the APG network (blue) and the borehole sensors (red) as a function of the centroid position of a hypothetical slip

3.15A Cross section showing the megathrust fault (labeled as “megasplay”), marking the convergent plate boundary between the subducting Philippine Sea plate and the overriding Eurasian plate off the coast of Japan

3.15B Summary of changes in pressure (ΔP) and strain (ε_v) measured at two boreholes (red and blue) near the Nankai trench off the coast of Japan

3.16 Within the vast expanse of the oceanic subseafloor biosphere, gigatons of deposited and buried carbon (Gt C) and an estimated 10²⁷–10²⁹ cells are present

3.17 Major net chemical fluxes due to microbial activities in subseafloor environments

3.18 Three main phases in the life cycle of an ocean plate

3.19 Cores of mantle rock from below the seafloor recovered from Expedition 399

3.20 Carbon dioxide sequestration experimentation

4.1 Capabilities of the current U.S. Academic Research Fleet (ARF) for subseafloor sampling

4.2 The impact of riserless drilling in access to global subseafloor depths

4.3 Highly sampled core from an interval of high scientific interest

4.4 The Extending Ocean Drilling Pursuits (eODP) data-integration system

TABLES

S.1 Connecting Scientific Ocean Drilling Priorities to U.S. National Priorities and Prior Study Recommendations to NSF

S.2 Available Assets Obtained from Select Scientific Ocean Drilling Programs to Advance Some Vital and Urgent Research Priorities

S.3 Parameters for Accomplishing Vital and Urgent Ocean Drilling Science Research Priorities

1.1 Expedition Statistics for the International Ocean Discovery Program (2013–2024)

2.1 Gender Demographics for U.S. Applications and Final Expedition Science Party Participation During IODP-2

2.2 U.S. IODP Science Parties by Career Level, 2015–2023

2.3 Generalized Pre- Through Post-Expedition Time Frames and Activities

3.1 Progress Made Toward Past Research Priorities

3.2 High-Priority Science Areas that Require Future Scientific Ocean Drilling

3.3 Connecting Scientific Ocean Drilling Priorities to U.S. National Priorities and Prior Study Recommendations to NSF

4.1 High-Priority Science Areas That Can and Cannot Be Addressed Using Existing Assets

4.2 Parameters for Accomplishing Vital and Urgent Ocean Drilling Science Research Priorities

Acronyms and Abbreviations