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“Methane Hydrates: An Earth System Science Perspective”

Capitol Hill Oceans Week 2003 Rayburn House Office Building - Washington, D.C. June 11, 2003. “Methane Hydrates: An Earth System Science Perspective”. Dr. Frank R. Rack, Joint Oceanographic Institutions 1755 Massachusetts Ave., NW; Suite 700; Washington, D.C. 20036-2102

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“Methane Hydrates: An Earth System Science Perspective”

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  1. Capitol Hill Oceans Week 2003 Rayburn House Office Building - Washington, D.C. June 11, 2003 “Methane Hydrates: An Earth System Science Perspective” Dr. Frank R. Rack, Joint Oceanographic Institutions 1755 Massachusetts Ave., NW; Suite 700; Washington, D.C. 20036-2102 Tel: (202) 939-1624; Fax: (202) 462-8754 Email: frack@joiscience.org http://www.joiscience.org

  2. General Outline of this Presentation • What are methane hydrates and where are they found? • Accomplishments of scientific ocean drilling (DSDP, ODP) in support of global, interdisciplinary methane hydrate research. • Key methane hydrate research topics and questions; industry perspective on methane hydrate resource potential. • What have we learned about naturally-occurring marine methane hydrates? Adopting an “Earth System Science” approach to methane hydrate research. • International, industry-led methane hydrate research and development projects (Gulf of Mexico, Japan, India). • Summary statement and acknowledgements.

  3. What are methane hydrates and how do they form? The term “methane hydrate” means: (A) a methane clathrate that is in the form of a methane-water ice-like crystalline material that is stable and occurs naturally in deep-ocean and permafrost environments; and, (B) other natural gas hydrates (e.g., ethane, higher order hydrocarbons) that are found in association with deep-ocean and permafrost deposits of methane hydrate. (Section 201 of the Mining and Minerals Policy Act of 1970, as amended by P.L. 106-193: Methane Hydrate Research & Development Act of 2000) • Methane + Water • Moderately High Pressures • Moderately Low Temperatures

  4. How much methane do hydrates contain? Hydrate provides very efficient storage of methane gas (ENERGY). When hydrate is brought to the surface from depth in the sediments about 164 times the volume of gas is released, along with a small quantity of water. Global estimates of the methane stored in hydrate deposits are as large as 700,000 TCF (trillion cubic feet of gas); U.S. potential resource estimates are from 100,000 to 300,000 TCF. Photo by Dr. Gary Klinkhammer Oregon State University

  5. Where are hydrates found?

  6. DSDP/ODP Achievements in Scientific Ocean Drilling Achievements in scientific ocean drilling have set the stage for understanding the complex linkages among the different parts of the dynamic Earth system (including methane hydrates). “The Deep Sea Drilling Project (DSDP: 1968-1983) validated the theory of plate tectonics, began to develop a high-resolution chronology associated with study of ocean circulation changes, and carried out preliminary exploration of all of the major ocean basins except the high Arctic. The Ocean Drilling Program (ODP: 1985-2003), capitalizing on DSDP’s momentum, probed deeper into the ocean crust to study its architecture, analyzed convergent margin tectonics and associated fluid flow, and examined the genesis and evolution of oceanic plateaus and volcanic continental margins. ODP has also greatly extended our knowledge of long- and short-term climate change.” “Earth, Oceans and Life” (2001) IODP Initial Science Plan, 2003-2013 For more information, see URL: http://www.iodp.org

  7. D/V JOIDES Resolution Research Vessel of the Ocean Drilling Program The JOIDES Resolution is a uniquely outfitted dynamically-positioned drill ship, that has a seven-story laboratory complex onboard. This vessel has used by the Ocean Drilling Program (ODP) since 1985 to conduct worldwide scientific coring operations.

  8. DSDP/ODP Studies of Naturally-Occurring Oceanic Methane Hydrate Deposits Leg 204 Hydrate Ridge Legs 11, 76 & 164 Blake Ridge Leg 201

  9. DSDP/ODP Methane Hydrate Research: Accomplishments (1970-1990) • 1970 - 1st BSR drilled, DSDP Leg 11: Blake Ridge (offshore Carolinas) • 1979 - hydrate samples observed in core, DSDP Leg 66: W. Mexican Margin • 1979 - hydrate samples preserved in LN2, DSDP Leg 67: Guatemala Margin • 1980 - 1st use of the Pressure Core Barrel (PCB), DSDP Leg 76: Blake Ridge • 1982 - 1.5 m-long massive hydrate sample recovered, DSDP Leg 84: • Guatemala Margin (used in cooperative federal hydrate research program) • 1983 - Microbiology & hydrates, DSDP Leg 96: Gulf of Mexico • 1986 - Hydrates in slope sediments; 1st scientific use of the wireline Pressure Core Sampler (PCS): ODP Leg 112: Peru Margin • 1989 - Hydrates in Sea of Japan, ODP Leg 127: offshore western Japan • 1990 - Hydrates in Nankai Trough, ODP Leg 131: offshore eastern Japan

  10. ODP Methane Hydrate Research: Accomplishments (1991-2003) • 1992 - Drilled through BSR (installed CORK), Leg 146: offshore Cascadia Margin (Vancouver Island to Oregon - N. Hydrate Ridge) • 1995 - 1st dedicated hydrate expedition, Leg 164: Blake Ridge (offshore Carolinas) - using geophysical data and drilling to test models • 1997 - LWD data from hydrate-bearing sediments, Leg 170: Costa Rican Margin (ground-truth and modeling of geophysical data) • 2000-2001 - accretionary prism, LWD, advanced CORK installations in a region with gas hydrates, Legs 190 and 196: Nankai Trough (offshore Japan) • 2002 - 1st dedicated microbiology expedition, Leg 201: Peru Margin (investigating interrelationships between hydrates and microbiology) • 2002 - 2nd dedicated hydrate expedition, Leg 204: southern Hydrate Ridge (offshore Oregon); additional funds provided by NSF, DOE/NETL, USGS, European Commission (HYACINTH project).

  11. Where is the gas hydrate stability zone in ocean sediments? Thermocline Figure courtesy of Dr. Bill Dillon (USGS, retired) and Hydrate Energy International (HEI)

  12. Where is the gas hydrate stability zone in ocean sediments? Figure courtesy of Dr. Bill Dillon (USGS, retired) and Hydrate Energy International (HEI)

  13. Mapping of bottom simulating reflector (BSR) and gas hydrate distribution - offshore eastern United States Location of slope stability slide presented later in talk Blake Ridge ODP Leg 164 Figure courtesy of Dr. Bill Dillon (USGS, retired) and Hydrate Energy International (HEI)

  14. Characteristics of bottom simulating reflector (BSR) ODP Leg 164 - Blake Ridge and Carolina Rise Figure courtesy of Dr. Steve Holbrook (University of Wyoming)

  15. What do naturally-occurring hydrates look like? Hydrate sample recovered during ODP Leg 164 on Blake Ridge

  16. Examples of gas hydrate distribution in sediment Figure courtesy of Dr. Tim Collett (USGS) and the National Research Council of Canada

  17. Methane Hydrate Natural Laboratory: Hydrate Ridge, Offshore Oregon - ODP Leg 204 Figure courtesy of Dr. Chris Goldfinger (Oregon State University) From Trehu, Bohrmann, Rack, et al., 2002. ODP Leg 204 Preliminary Report Figures courtesy of Dr. Bill Dillon (USGS, retired) and Hydrate Energy International (HEI)

  18. Instrumented Borehole Observatories for Hydrate Studies

  19. Methane Hydrate Research and Development Act of 2000 (P.L. 106-193) – Interagency (DOE, DOI, DOD, DOC, NSF) Methane Hydrate Research Program – Key Questions: • Resource Characterization - What are the quantities, locations, and properties of naturally-occurring hydrate? • Safety and Seafloor Stability - What is needed to ensure safety and mitigate the environmental impacts of hydrate? • Global Climate Change - What are the environmental impacts and the role of hydrate in the global carbon cycle? • Hydrocarbon Production - What is required to produce commercial quantities of methane gas from hydrates? Questions modified from DOE/NETL National Hydrate R&D Program overview presentation, Brad Tomer, August 2000.

  20. Resource Characterization and Economic Potential: How does industry evaluate a commercial hydrate prospect? • hydrocarbon source, timing, and migration pathways; reservoir rock, seal, stratigraphic or structural trap • infrastructure (e.g., rigs, pipelines; if already in place, then huge benefit) • access to acreage (exploration and exploitation regulatory framework) • economic production technology (e.g., passive and/or active production methods: (1) natural hydrate dissociation, (2) lower pressure of formation, (3) add heat energy, or (4) inject solvents - ethanol, glycol) • recoverability - rate that selected production method(s) can safely get the gas from hydrate out of the ground with minimal environmental impact • basic economic metric = gas recovered per well drilled (taking into account the daily production rate; operating cost; market price of gas; competition with other sources of conventional energy) • Expected Value = Potential Revenues - Production Cost + Risk Summary provided by Dr. Art Johnson (Chevron, retired) and Hydrate Energy International (HEI)

  21. How might gas hydrates influence slope stability? Mapping of submarine slope failures shows a strong relationship between sediment mass movements and the presence of gas hydrate. Figure courtesy of Dr. James Booth (USGS) and Naval Research Laboratory (NRL)

  22. How might gas hydrates influence slope stability? Figure courtesy of Dr. Bill Dillon (USGS, retired) and Hydrate Energy International (HEI)

  23. Migration of gas along faults and hydrate formation Figure courtesy of Dr. Ian MacDonald (Texas A&M University, Corpus Christi) Figure courtesy of Dr. Bill Dillon (USGS, retired) and Hydrate Energy International (HEI)

  24. Biogeochemical Cycles and Chemosynthetic Communities: An Earth System Science Approach Trehu, Bohrmann, Rack, et al., 2002. ODP Leg 204 Preliminary Report

  25. Biogeochemical and Fluid Processes on Continental Margins: An Earth System Science Approach Microbial methanogenesis Thermogenic hydrocarbon migration from depth

  26. V o l c a n o e s O r g a n i c O x i d a t i o n B i o m a s s A t m o s p h e r e C a r b o n a t e & W a r m S u r f a c e W a t e r S i l i c a t e C o l d W e a t h e r i n g S . W . O r g a n i c T h e r m o c l i n e C a r b o n B u r i a l C a r b o n a t e D e e p O c e an How are hydrates incorporated into carbon cycle models? Conventional Global Carbon Cycle Accumulation Modified from Dickens, AGU Monograph 124, 2001

  27. V o l c a n o e s O r g a n i c O x i d a t i o n B i o m a s s A t m o s p h e r e C a r b o n a t e & W a r m S u r f a c e W a t e r S i l i c a t e C o l d W e a t h e r i n g S . W . O r g a n i c T h e r m o c l i n e C a r b o n B u r i a l C a r b o n a t e D e e p O c e an OH• Oxidation Accumulation Anaerobic CH4 oxidation or direct injection of free gas Aerobic Oxidation Methanogenesis of organic matter and saturation of pore waters to form hydrate Gas Hydrate Temp. Free Gas Modified from Dickens, AGU Monograph 124, 2001

  28. What have we learned about gas hydrate? • Hydrate is a frozen crystalline solid consisting of “cages” of water molecules that surround and hold gas molecules (primarily methane) inside. • Hydrate formation requires a source of carbon (e.g., methane gas - CH4), fresh water, moderately low temperatures and moderately high pressures. • Hydrate deposits are widespread along many continental margins, from the seafloor to the base of the hydrate stability zone in water depths greater than about 500 meters, and in the Arctic below the permafrost. Free gas may be present below the zone of hydrate stability in many areas. • Hydrate deposits contain a huge quantity of stored carbon – estimated to be about 2 times the amount of carbon stored in all known hydrocarbon resources (petroleum, natural gas, and coal, as well as less economic resources contained in tar sands and oil shales). • Estimates of the global distribution and volume of hydrates are largely based on geophysical mapping and interpretation, modeling results, and limited “ground truth” provided by coring and drilling.

  29. What have we learned about gas hydrate? • Hydrate is unstable at Earth surface conditions (i.e., material will change from a solid to a gas when removed from the gas hydrate stability zone). • Hydrate deposits in seafloor sediments may influence slope stability. Submarine slope failure and the mass movement of sediment may result from the destabilization of subsurface hydrate deposits following a change in stability conditions (e.g., change in pressure or temperature). • Hydrates are an unconventional (potential) energy resource. Industry seeks to understand hydrates to improve operational safety and to avoid hazards (e.g., placement of infrastructure on seafloor, drilling and production scenarios) as well as to understand their resource potential. • Low concentrations of hydrate are associated with shales (fine-grained sediments, low energy environments): resource potential is probably low. • High concentrations of hydrate are associated with sands (coarse-grained sediments, high energy environments): higher potential for future hydrate exploration and production efforts due to higher porosity and permeability.

  30. Potential Methane Hydrate Prospects Offshore USA: Gulf of Mexico - Outer Continental Shelf and Slope

  31. Potential Methane Hydrate Prospects Offshore Japan MITI Nankai Trough (1999) Figure courtesy of Dr. Yuichiro Ichikawa (Japan National Oil Corporation)

  32. 6600 7000 7400 7800 8200 8500 9000 9400 2200 2200 1800 1800 1400 1400 1000 1000 9000 6600 7000 7400 7800 8200 9400 8500 Potential Methane Hydrate Prospects Offshore India Figure courtesy of Dr. Pushpendra Kumar (Oil and Natural Gas Corporation, India)

  33. Methane Hydrate Research Needs • The rates of hydrate formation and dissociation, the periods over which the deposits have formed, as well as their interactions with microorganisms are not well understood. Without such an understanding, it is impossible to accurately model the global carbon cycle and to effectively model the dynamics and global consequences of natural hydrate deposits. Integrated, multi-disciplinary scientific expeditions are essential for addressing these fundamental research questions about hydrates. • Detailed, high-quality geophysical data (e.g., 2-D and 3-D multi-channel seismic, multi-beam bathymetry, side-scan sonar surveys) and are needed to quantify and characterize the distribution and geoacoustic properties of hydrates on continental margins. Settings with different rates of hydrate formation and dissociation and different modes of methane transport must then be drilled to provide “ground truth” and observational data to support geophysical and model interpretations. • Long-term monitoring of in situ pressure, temperature, fluid flow and other fundamental properties and processes related to hydrate deposits is required (e.g., using instrumented boreholes and seafloor observatories) to understand and quantify hydrate dynamics and to improve models. Integrated database development is essential for the success of these activities (e.g., need capability for data fusion).

  34. Future Scientific Ocean Drilling Plans and ICEY HOPE The Integrated Ocean Drilling Program (IODP) will be established with funding from NSF (U.S.), MEXT (Japan), and other international partners beginning in October 2003. Scientific planning for IODP is underway. The Initial Science Plan for IODP includes focused studies of the “Deep Biosphere and the Subseafloor Ocean” with an initiative on gas hydrates (for more information see: http://www.iodp.org). “Interdisciplinary Collaborative Expeditions for a Year of Hydrate Observations and Perturbation Experiments” (ICEY HOPE):Initial concept for a series of exploratory ocean drilling expeditions to establish a globally distributed array of instrumented borehole sites which can be used to monitor naturally-occurring hydrates from a range of marine environments (e.g., low to high flux) to assess rates, reduce uncertainties, and improve fundamental understanding of dynamic biogeochemical and physical processes through time-series measurements, sensor deployments, perturbation experiments, and integrated interdisciplinary process studies.

  35. Acknowledgements The information presented in this talk represents a synthesis of the hydrate research efforts and presentations made by a large number of colleagues and collaborators. In particular, I would like to thank the following individuals for their contributions: William Dillon (USGS, retired), Arthur Johnson (Chevron, retired), and Michael Max (formerly at NRL), all presently at Hydrate Energy International (HEI); Tim Collett (USGS, Denver); Scott Dallimore (Geological Survey of Canada); Keith Kvenvolden, Tom Lorenson, Steve Kirby, Laura Stern (USGS, Menlo Park); Bill Winters, Bill Waite, Debbie Hutchinson (USGS, Woods Hole); Charles Paull and William Ussler (Monterey Bay Aquarium Research Institute); Dendy Sloan (Colorado School of Mines); Carolyn Ruppel (Georgia Institute of Technology); Gerald Dickens (Rice University); Miriam Kaster (Scripps Institution of Oceanography); Mahlon “Chuck” Kennicutt, William Bryant, Roger Sassen, William Sager (Texas A&M University); Ian MacDonald (Texas A&M University - Corpus Christi); Steve Holbrook (University of Wyoming); Jean Whelan (Woods Hole Oceanographic Institution); Harry Roberts (Louisiana State University); Tom McGee and Robert Woolsey (University of Mississippi); Emrys Jones, Ben Bloys, James Schumacher (ChevronTexaco); Tom Williams (Maurer Technology/Noble Drilling Corporation); Yuichiro Ichikawa (Japan National Oil Corporation); Pushpendra Kumar (Oil and Natural Gas Corporation, India); and the scientists, engineers, and technical staff onboard ODP Leg 204 (see following slide). I would also like to acknowledge the financial support and encouragement provided by the U.S. National Science Foundation, Ocean Drilling Program and the U.S. Department of Energy, National Energy Technology Laboratory to Joint Oceanographic Institutions.

  36. ODP Leg 204 Participants Co-Chief Scientists: Gerhard Bohrmann (GEOMAR, Christian-Albrechts Universitat zu Kiel, Germany) and Anne M. Trehu (Oregon State University); Staff Scientist: Frank Rack (Joint Oceanographic Institutions); Shipboard Scientists: Walter S. Borowski (Eastern Kentucky University), Hitoshi Tomaru (University of Tokyo, Japan), Marta E. Torres (Oregon State University), George E. Claypool (Consultant, Lakewood CO), Young-Joo Lee (Korea Institute of Geoscience and Mineral Resources, Korea), Alexei Milkov (Texas A&M University), Gerald R. Dickens (Rice University), Timothy S. Collett (U.S. Geological Survey, Denver), Nathan Bangs (University of Texas at Austin), Martin Vanneste (University of Tromso, Norway), Melanie Holland (Arizona State University), Mark E. Delwiche (Idaho National Engineering and Environmental Laboratory), Mahito Watanabe (Geological Survey of Japan, AIST, Japan), Char-Shine Liu (National Taiwan University, Taiwan), Philip E. Long (Pacific Northwest National Laboratory), Michael Riedel (Geological Survey of Canada, Pacific Geoscience Centre, Canada), Peter Schultheiss (GEOTEK Ltd., United Kingdom), Eulalia Gracia (Institute of Earth Sciences, CSIC, Barcelona, Spain), Joel E. Johnson (Oregon State University), Xin Su (China University of Geosciences, People’s Republic of China), Barbara Teichert (GEOMAR, Christian-Albrechts Universitat zu Kiel, Germany), Jill L. Weinberger (Scripps Institution of Oceanography, University of California, San Diego), David S. Goldberg (Lamont-Doherty Earth Observatory, Columbia University), Samantha R. Barr (University of Leicester, United Kingdom), Gilles Guèrin (Lamont-Doherty Earth Observatory, Columbia University); Shipboard Engineers: Michael A. Storms, Derryl Schroeder, and Kevin Grigar (Ocean Drilling Program, Texas A&M University), Roeland Baas and Floris Tuynder (Fugro Engineers, The Netherlands), Felix Weise (Technical University of Clausthal, Germany), Thjunjoto (Technical University of Berlin, Germany), Terry Langsdorf and Ko-Min Tjok (Fugro-McClelland Engineers, USA), Kerry Swain, Herbert Leyton, Stefan Mrozewski and Khaled Moudjeber (Schlumberger Offshore Services, USA); Shipboard Technical Staff: Brad Julson, Tim Bronk, Angie Miller, John Beck, Roy Davis, Jason Deardorf, Sandy Dillard, Dennis Graham, Jessica Huckemeyer, Margaret Hastedt, Brian Jones, Peter Kannberg, Jan Jurie Kotze, Erik Moortgat, Peter Pretorius, John W.P. Riley, Johanna Suhonen, Paul Teniere, Robert Wheatley (all at Ocean Drilling Program, Texas A&M University)

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