Carolyn Ruppel, PhD

My primary research focus is on the interaction between methane hydrates (and methane seeps) on one hand and the ocean-atmosphere system on the other.  I focus particularly on the US Atlantic and US Pacific margins, as well as Arctic Ocean margins (US Beaufort Sea and Svalbard). I also work on energy issues related to gas hydrates (including delineating their distribution in marine sediments; 2018 MATRIX seismic program on US Atlantic margin), the coexistence of permafrost (including subsea) and hydrates (Beaufort Sea), and reservoir properties of hydrate-bearing sediments.  As a side specialty, I assist with programmatic environmental compliance for USGS marine acoustics surveys.  During my career, I have also worked on marine heat flow data acquisition and analysis, other aspects of the hydrogeology of gas hydrate systems, and coastal zone hydrogeophysics (particularly tidal pumping, inductive EM data, and saline intrusion in surficial aquifers).  My earliest work focused on numerical modeling of large scale tectonic processes and associated particle tracking, continental rifting, and marine analogs for continental tectonic processes.  Google scholar page: https://scholar.google.com/citations?hl=en&user=FIhPCKcAAAAJ

EDUCATION

Massachusetts Institute of Technology, Ph.D., 1992, Geophysics and Geology (with Marcia McNutt)

Massachusetts Institute of Technology, M.S., 1986, Earth sciences (with Leigh Royden and Kip Hodges)

Massachusetts Institute of Technology, B.S., 1986, Earth sciences

PROFESSIONAL EXPERIENCE

2010-present: Chief, USGS Gas Hydrates Project

2006-present: Research Geophysicist, U.S. Geological Survey

2006- present: Visiting Scientist, MIT, Dept. of Earth, Atmospheric & Planetary Sciences

2003-2006: Program manager (faculty rotater), National Science Foundation, Ocean Sciences (MG&G and Ocean Drilling Program)

2000-2002: Coordinator, Georgia Tech Focused Research Program on Methane Hydrates

2000-2006: Associate Professor of Geophysics (tenured), Georgia Institute of Technology

1994-2000: Assistant Professor of Geophysics, Georgia Institute of Technology

1993: Postdoctoral Investigator, Woods Hole Oceanographic Institution (advisor: Von Herzen)

1992: Postdoctoral Scholar, Woods Hole Oceanographic Institution (advisors: Lin, Von Herzen)

SELECTED ACTIVITIES

Writing Team, OSTP group for Section 4 of the Presidential Memorandum on Marine Mapping, 2019-2020

Member, Arctic Icebreaker Coordinating Committee (UNOLS), 2015-2020  (ex officio: 2020 - present)

Chief Scientist, 8 research cruises (3 Arctic), 2010-2019

Member, Advisory Board, University of Tromso, Centre of Excellence for Arctic Gas Hydrate, Environment and Climate (CAGE) 2014-present

Strategic Plan Committee, Coastal & Marine Geology Program, USGS, 2014-2019

Arctic subgroup (appointed CMGP representative), Subcommittee on Ocean Science and Technology (SOST), OSTP, 2015-16

Mentor, Graduate Women at MIT (GWAMIT), 2013-2016

USGS Technical lead, NSF-USGS Programmatic Environmental Impact Statement for Marine Seismics, 2008-2012

Lead proponent, IODP Pre-Proposal 797, Late Pleistocene to contemporary climate change on the Alaskan Beaufort Margin (ABM)

Lead organizer, Catching climate change in progress, circum-Arctic Ocean drilling workshop, December 2011 (sponsored by US Science Support Program for IODP)

Organizer and convener, USGS-DOE Climate-Hydrates workshop, Boston, MA, March 2011

Originator and Chair, Gordon Research Conference on Natural Gas Hydrates, inaugural conference held June 2010.

Interagency Technical Coordinating Committee, DOE Methane Hydrates R&D Program, 2010-present

The Future of Natural Gas, MIT Energy Initiative, affiliated author (methane hydrates), 2008-2011

National Research Council, Scientific Ocean Drilling (SOD) review, presentation on Gas Hydrates and SOD, 2010

IODP Operations Task Force, 2008-2009

IODP Science Planning Committee (SPC), 2006-2009

Organizer, DOE-USGS Symposium/Meeting on Gas Hydrates and Climate Change (held at MIT), February 2008

Organizing Committee, NSF-sponsored workshop--The Future of Marine Heat Flow: A Workshop to Define U.S. Scientific Goals and Experimental Needs for the 21st Century, Sept. 2007

USGS representative to WHOI Postdoctoral Scholar Committee, 2007

DOE Federal Advisory Board for Methane Hydrates (FACA committee), 2001-2003

ODP U.S. Science Advisory Committee (USSAC), 2000-2003

AGU Publications Committee, 2002-2003

NSF Methane in Earth Systems History (MESH) program planning panel, 2002

NSF Ocean Carbon Cycle Panel(program planning), 2001-2002

ODP Hydrogeology Proposal Planning Group (PPG), liaison on gas hydrates, 2001-2002

ODP Gas Hydrates Proposal Planning Group (PPG), liaison from SSEP, 1998-99

ODP Science Steering and Evaluation Panel (SSEP Earth's Interior), 1997-1999

AGU Information Technology Committee, 1996-1998

AGU Spring Meeting Organizing Committee, Tectonophysics Section Chair, 1999

Co-organizer of AGU special sessions on gas hydrates: 1999, 2001, 2005 (Union)

Co-organizer of AGU special sessions on coastal hydrogeophysics: 1999, 2001, 2005

AGU Translations Board, 1994-1996

EDITORIAL ASSIGNMENTS

Co-Guest Associate Editor, Special Issue on the Reservoir Properties of Hydrate-Bearing Sediments, Journal of Geophysical Research, 2017-2019

Co-Editor, Special Volume on Nankai Gas Hydrates Drilling, Journal of Marine and Petroleum Geology, 2014-2015

Expert Reviewer, UN Environmental Programme report on methane hydrates, Volume 1, 2013-14

Lead editor, special volume, Marine & Petroleum Geology, DOE-JIP Gulf of Mexico gas hydrates drilling, 2006-2008

Hydrogeology Journal, editorial board, 2005-2007

Geology, editorial board, 2000-2003

Tectonics, Associate Editor, 1996-1999

Fiziki Zemli, oversight responsibility for AGU publication in translation, 1994-1996

AWARDS AND HONORS

National Science Foundation, Director's Award for Program Management, 2005 (Chixulub seismic program)

JOI/USSAC Distinguished Lecturer, Ocean Drilling Program, 1999-2000

Elected Geological Society of America (GSA) Fellow, 1999

Class of 1969 Teaching Fellow, Georgia Tech, 1994-1995

Postdoctoral scholar, WHOI, Geology & Geophysics, 1992

PUBLICATIONS

Hassanpouryouzband, A., Joonaki, E., Farahani, M.V., Takeya, S., Ruppel, C., Yang, J., English, N.J., Schicks, J.M., Edlmann, K., Hadi, Mehrabian, H., Aman, Z.M., and B. Tohidi (2020--in press), Gas Hydrates in Sustainable Chemistry, Chem. Soc. Rev., Royal Society of Chemistry.

Leonte, M., Ruppel, C. D., Ruiz‐Angulo, A., & Kessler, J. D. ( 2020). Surface Methane Co Along the Mid‐Atlantic Bight Driven by Aerobic Subsurface Production Rather Than Seafloor Gas Seeps. Journal of Geophysical Research: Oceans, 125, e2019JC015989. https://doi.org/10.1029/2019JC015989

[data release] Ruiz-Angulo, Angel; Ruppel, Carolyn D.; Hatcher, Gerald; Kessler, John D. (2020). Current velocities as a function of depth measured by lowered ADCP, LADCP, on the research vessel Hugh R. Sharp in the Mid-Atlantic Bight from 2017-08-26 to 2017-09-03 (NCEI Accession 0209236). NOAA National Centers for Environmental Information. Dataset. https://accession.nodc.noaa.gov/0209236.

[data release] Baldwin, W.E., Moore, E.M., Worley, C.R., Nichols, A.R., and Ruppel, C.D., 2020, Marine geophysical data collected to support methane seep research along the U.S. Atlantic continental shelf break and upper continental slope between the Baltimore and Keller Canyons during U.S. Geological Survey Field Activities 2017-001-FA and 2017-002-FA: U.S. Geological Survey data release, https://doi.org/10.5066/P9Y1MSTN.

[data release] Overduin, P. P. , Schneider von Deimling, T. , Miesner, F. , Grigoriev, M. N. , Ruppel, C. D. , Vasiliev, A. A. , Lantuit, H. , Juhls, B. , Westermann, S. and Laboor, S. (2020): Submarine Permafrost Map (SuPerMAP), modeled with CryoGrid 2, Circum-Arctic https:doi.org/10.1594/PANGAEA.910540

Ruppel, C., Lee, J. Y., & Pecher, I. ( 2019). Introduction to special issue on gas hydrate in porous media: Linking laboratory and field‐scale phenomena. Journal of Geophysical Research: Solid Earth, 124. https://doi.org/10.1029/2019JB018186

Ruppel, C. D., Lachenbruch, A. H., Hutchinson, D. R., Munroe, R. J., & Mosher, D. C. ( 2019). Heat flow in the Western Arctic Ocean (Amerasian Basin). Journal of Geophysical Research: Solid Earth, 124. https://doi.org/10.1029/2019JB017587

[data release] Lachenbruch, A.H., Marshall, B.V., and Ruppel, C.D., 2019, Post-expedition report for USGS T-3 Ice Island heat flow measurements in the High Arctic Ocean, 1963-1973: U.S. Geological Survey data release, https://doi.org/10.5066/P91XQ3IS

[data release] Ruppel, C.D., Hutchinson, D.R., Lachenbruch, A.H., and Hall, J.K., 2019, Thermal data and navigation for T-3 (Fletcher's) Ice Island Arctic Ocean heat flow studies, 1963-73: U.S. Geological Survey data release, https://doi.org/10.5066/P97EPU2F.

Ruppel, C., N.C. Miller, M. Frye, W. Baldwin, D. Foster, W. Shedd, and S. Palmes, 2019, U.S. Mid-Atlantic resource imaging experiment (MATRIX) constrains gas hydrate distribution, Fire in the Ice: DOE NETL Methane Hydrates newsletter, 19(1), pp. 6-8. https://www.netl.doe.gov/sites/default/files/publication/MHNews_2019_Spring.pdf

Overduin, P. P., Schneider von Deimling, T., Miesner, F., Grigoriev, M. N., Ruppel, C., Vasiliev, A., et al., 2019, Submarine Permafrost Map in the Arctic Modelled Using 1D Transient Heat Flux (SuPerMAP). Journal of Geophysical Research: Oceans, 124.  https://doi.org/10.1029/2018JC014675

Demopoulos, A., J. McClain-Counts, J. Bourque, N. Prouty, B. Smith, S.D. Brooke, S. Ross, and C. Ruppel, 2019, Examination of Bathymodiolus childressi nutritional sources, isotopic niches, and food-web linkages at two seeps in the US Atlantic margin using stable isotope analysis and mixing models, Deep Sea Research I, 148, 53-66, https://doi.org/10.1016/j.dsr.2019.04.002

[data release] Brothers, L.L., C.D. Ruppel, P.E. Hart, and B.M. Herman, 2019, Minimal offshore extent of ice-bearing (subsea) permafrost on the U.S. Beaufort Sea margin, USGS Data Release, https://doi.org/10.5066/P96FB9F7

Miller, N.C., W. Baldwin, and C. Ruppel, 2018, USGS images gas hydrates with 2000 km of new seismic data on U.S. Atlantic margin, Sound Waves CMHRP newsletter, November 2018, https://archive.usgs.gov/archive/sites/soundwaves.usgs.gov/2018/11/index.html.

Waite, W.F., C.D. Ruppel, T.S. Collett, P. Schultheiss, M. Holland, K.M. Shukla, P. Kumar, 2018, Multi-measurement approach for establishing the base of gas hydrate occurrence in the Krishna-Godavari Basin for sites cored during expedition NGHP-02 in the offshore of India, Marine and Petroleum Geology, doi: 10.1016/j.marpetgeo.2018.07.026

Kessler, JK, C Ruppel, DJ Joung, F Garcia-Tigreros, M Leonte, 2018, Exploring Impacts of Widespread Seafloor Methane Seepage on Ocean Chemistry and Atmospheric Methane Emissions along the U.S. Mid-Atlantic Margin, DOE Fire in the Ice hydrates newsletter, pp 4-6.

Ruppel, C., A. Demopoulos, and N. Prouty, 2018, Exploring US Mid-Atlantic Margin Methane Seeps: IMMeRSS, May 2017, Supplement to Oceanography, 31(1), p. 97.

Ruppel, C., 2018, Gas Hydrate in Nature, USGS Fact Sheet 3079.

Ruppel, C., 2018, The U.S. Geological Survey's Gas Hydrates Project, USGS Fact Sheet 3080.

Sparrow, K., J.D. Kessler, J.R. Southon, F. Garcia-Tigreros, K.M. Schreiner, C.D. Ruppel, J.B. Miller, S.J. Lehman, and X. Xu, 2018, Limited contribution of ancient methane to surface waters of the U.S. Beaufort Sea, Science Advances, 4.

Ruppel, C., A. Demopoulos, N. Prouty, D. Sahy, and D. Condon (2017), Exploring U.S. Atlantic margin seeps with a  remotely-operated vehicle, U.S. Dept. of Energy, National Energy Technology Lab, DOE NETL Fire in the Ice newsletter, 17(2), 12-15.

Toran, A., C. Ruppel, A. Demopoulos, and N. Prouty (2017), Real-time public engagement in deep-water remotely operated vehicle dives at methane seeps, Sound Waves CMGP newsletter, https://soundwaves.usgs.gov/2017/05/outreach.html.

Pohlman, J., J. Greinert, C. Ruppel, A. Silyakova, L. Vielstadte, M. Casso, J. Mienert, and S. Bunz (2017), Enhanced CO₂ uptake at a shallow Arctic Ocean seep field overwhelms the positive warming potential of methane, Proc. Nat. Acad. Sci., doi: http://www.pnas.org/content/early/2017/05/02/1618926114.

(Data release)  Ruppel, C., Pohlman, J., and M. Casso (2017), Data and calculations to support the study of the sea-air flux of methane and carbon dioxide on the West Spitsbergen margin in June 2014: U.S. Geological Survey data release, https://doi.org/10.5066/F7M906V0.

Waite, W.F., T. Weber, X. Fu, R. Juanes, and C. Ruppel (2017), Laboratory observations of the evolution and rise rate of bubbles with and without hydrate shells, Proc. 9^th Int. Conf. on Gas Hydrates, Denver, 14 pp.

Ruppel, C., L. Brothers, and P. Hart (2017), Subsea permafrost and associated methane hydrate on the U.S. Arctic Ocean margin, Sound Waves CMGP newsletter, https://soundwaves.usgs.gov/2017/04/research.html.

Ruppel, C. D., and J. D. Kessler (2017), The interaction of climate change and methane hydrates, Rev. Geophys., 55, 126-168, doi:10.1002/2016RG000534.

Ruppel, C. D., B. M. Herman, L. L. Brothers, and P. E. Hart (2016), Subsea ice-bearing permafrost on the U.S. Beaufort Margin: 2. Borehole constraints, Geochem. Geophys. Geosyst., 17, 4333–4353, doi:10.1002/2016GC006582.

Brothers, L. L., B. M. Herman, P. E. Hart, and C. D. Ruppel (2016), Subsea ice-bearing permafrost on the U.S. Beaufort Margin: 1. Minimum seaward extent defined from multichannel seismic reflection data, Geochem. Geophys. Geosyst., 17, 4354–4365, doi:10.1002/2016GC006584.

Weinstein, A., L. Navarrete, C. Ruppel, T. C. Weber, M. Leonte, M. Y. Kellermann, E. C. Arrington, D. L. Valentine, M. I. Scranton, and J. D. Kessler (2016), Determining the flux of methane into Hudson Canyon at the edge of methane clathrate hydrate stability, Geochem. Geophys. Geosyst., 17, 3882–3892, doi:10.1002/2016GC006421.

(Data Release) Prouty, N.G., Sahy, D., Condon, D., Roark, E.B., Ruppel, C., and Demopoulos, A.W.J., 2016, Geochemical analysis of authigenic carbonates and chemosynthetic mussels at Atlantic Margin seeps: U.S. Geological Survey data release, http://dx.doi.org/10.5066/F77942SJ.

Prouty, N.G.; D. Sahy, C.D. Ruppel, E.B. Roark, D. Condon, S. Brooke, S.W. Ross, A.W.J. Demopoulos, 2016, Insights into methane dynamics from analysis of authigenic carbonates and chemosynthetic mussels at newly-discovered Atlantic Margin seeps, Earth and Planetary Science Letters, doi:10.1016/j.epsl.2016.05.023.

Scandella, B. P., L. Pillsbury, T. Weber, C. Ruppel, H. F. Hemond, and R. Juanes, 2016, Ephemerality of discrete methane vents in lake sediments, Geophys. Res. Lett., 43, 4374-4381, doi:10.1002/2016GL068668.

Quattrini AM, Nizinski MS, Chaytor JD, Demopoulos AWJ, Roark EB, France SC, Moore JA, Heyl, T, Auster, PJ, Kinlan, B., Ruppel, C., Elliot, K.P., Kennedy, B.R.C., Lobecker, E., Skarke, A., and Shank, T.M., 2015, Exploration of the Canyon-Incised Continental Margin of the Northeastern United States Reveals Dynamic Habitats and Diverse Communities. PLoS ONE 10(10): e0139904. doi:10.1371/journal.pone.0139904

Ruppel, C., Kluesner, J., Pohlman, J., Brothers, D., Colwell, F., Krause, S., and Treude, T., 2015, Methane hydrate dynamics on the Northern US Atlantic margin, DOE NETL Fire in the Ice newsletter, pp 10-13.

Yamamoto, K. and C. Ruppel, editors, 2015, plus Preface for...Gas Hydrate Drilling in Eastern Nankai, Journal of Marine and Petroleum Geology, 66(2), 295-496. doi:10.1016/j.marpetgeo.2015.08.026

Hatcher, G., J. White, P. Dal Ferro, and C. Ruppel, 2015, Sampling methane seeps and plumes on the US Atlantic margin, Sound Waves, USGS newsletter, Oct/Nov 2015.

Ruppel, C., Kluesner, J., and W. Danforth, 2015 Imaging methane seeps on the US Atlantic margin, Sound Waves, USGS newsletter, June 2015.

Ruppel, C., 2015, Permafrost-Associated Gas Hydrate: Is it Really ~1% of the Global System?, for: Special Issue in honor of E. Dendy Sloan on the occasion of his 70th Birthday, Journal of Chemical & Engineering Data, 60, 429-436 doi: 10.1021/je500770m

Phrampus, B., M. Hornbach, C. Ruppel, and P. Hart, 2014, Widespread gas hydrate instability on the upper U.S. Beaufort margin, J. Geophys. Res., 119, doi:10.1002/2014JB011290.

Skarke, A., C. Ruppel, M. Kodis, D. Brothers, and E. Lobecker, 2014, Widespread methane leakage from the seafloor on the northern US Atlantic margin, Nature Geoscience, doi:10.1038/ngeo2232. See also: Atlantic margin seeps.

Ruppel, C. and H. Hamilton, 2014, Natural methane seepage is widespread on the US Atlantic margin, Sound Waves newsletter, Oct/Nov 2014.

Haines, S.S., Hart, P.E., Ruppel, C.D., O'Brien, Thomas, Baldwin, Wayne, White, Jenny, Moore, Eric, Dal Ferro, Pete, and Lemmond, Peter, 2014, Cruise report for P1-13-LA, U.S. Geological Survey gas hydrates research cruise, R/V Pelican April 18 to May 3, 2013, deepwater Gulf of Mexico, U.S. Geological Survey Open-File Report 2014-1080, 33 p., http://dx.doi.org/10.3133/ofr20141080.

Porubsky, W.P., N.B. Weston, W.S. Moore, C. Ruppel, and S.B. Joye, 2014, Dynamics of submarine groundwater discharge and associated fluxes of dissolved nutrients, carbon, and trace gases to the coastal zone (Okatee River estuary, South Carolina), Geochim. Cosmo. Acta, doi:10.1016/j.gca.2013.12.030

Brothers, D.S., Ruppel, C., Kluesner, J.W., ten Brink, U.S., Chaytor, J.D., Hill, J.C., Andrews, B.D. and Flores, C., 2014, Seabed fluid expulsion along the upper slope and outer shelf of the U.S. Atlantic continental margin, Geophys. Res. Lett., doi: 10.1002/2013GL058048

Ruppel, C. and A. Demopoulos, 2013,  Chemosynthetic communities and gas hydrates at cold seeps south of Nantucket, July 11/12 ROV dive log.

Hunt, A.G., Stern, L., Pohlman, J.W., Ruppel, C., Moscati, R.J., and Landis, G., 2013, Mass fractionation of noble gases in synthetic methane hydrate: Implications for naturally occurring gas hydrate dissociation, Chemical Geology, 339, pp. 242-250, doi: 10.1016/j.chemgeo.2012.09.033.

Chaytor, J., A. Demopoulos, and C. Ruppel, 2013, Exploring undersea terrain off the northern US Atlantic coast via telepresence-enabled research cruise, Sound Waves, Nov/Dec 2013.

Haines, S., P. Hart, and C. Ruppel, 2013, New seismic data acquired over known gas hydrate occurrences in the deepwater Gulf of Mexico, U.S. Dept. of Energy, National Energy Technology Lab, "Fire in the Ice", 13(2), 3-6.

Hunt, A.G., C. Ruppel, L. Stern, and J. Pohlman, 2013, Using noble gas signatures to fingerprint gas streams derived from dissociating methane hydrate,U.S. Dept. of Energy, National Energy Technology Lab, "Fire in the Ice", 13(2), 23-26.

Nisbet, E., G. Allen, M. Cain, E. Dlugokencky, R. Fisher, J. France, M. Gallagher, D. Lowry, C. Lund Myhre, T. Minshull, J. Pyle, C. Ruppel, N. Warwick, G. Westbrook, and D. Worthy, Response of methane sources to rapid Arctic warming, Letter to the Editor, Nature. Full text not published by Nature, but available here

Hart, P., S. Haines, and C. Ruppel, 2013, Seismic-imaging research cruise investigates deepwater gas hydrate deposits in the Gulf of Mexico, Sound Waves, July/Aug. 2013.

Ruppel, C., J. Robertson, and B. Pierce, 2013, Groundbreaking gas hydrate research, Sound Waves, March/April 2013.

Brothers, L.L., C.L. Van Dover, C.R. German, C.L. Kaiser, D.R. Yoerger, C.D. Ruppel, E. Lobecker, A.D. Skarke, and J.K.S. Wagner, 2013, Evidence for extensive methane venting on the southeastern U.S. Atlantic margin, Geology, G34217.1, doi:10.1130/G34217.1.

Ruppel, C., 2013, Catching climate change in progress: Drilling on Circum-Arctic Shelves and Upper Continental Slopes, USSSP Workshop Report, 44 pp.

Ruppel, C. and T. Collett, 2013, Geological studies of methane hydrates reveal reserves with potential, Energy Focus, Fall edition, pp. 202-204. (http://energy-focus.co.uk/)

Brothers, L., P. Hart, and C. Ruppel, 2012, Minimum distribution of subsea ice-bearing permafrost on the US Beaufort Sea continental shelf, Geophys. Res. Lett., 39, L15501. Doi:10.1029/2012GL052222.

Ruppel, C., L. Brothers, P. Hart, C. Maue, J. Pohlman, J. Kessler, K.J. Sparrow, and C. Worley, 2012, Methane dynamics associated with long-term climate change on the Alaskan Beaufort Sea inner shelf, Fire in the Ice, DOE NETL newsletter, vol. 12(1), 7-10.

Ruppel, C., 2011, Methane Hydrates and Contemporary Climate Change, Nature Education Knowledge, 3(10):29.

Ruppel, C., 2012, Scientific drilling for climate-related objectives on Arctic Ocean margins (workshop report), EOS Trans. AGU, 93(22), 213.

Ruppel, C. and 12 others, Alaskan Beaufort Margin: Investigating the Impact of Warming Since the Last Glacial Maximum on Climate-Sensitive Sediments in the Arctic, IODP Pre-Proposal 797, submitted April 2012.

Ruppel, C. and D. Noserale, 2012, Gas hydrates and climate warming--Why a methane catastrophe is unlikely, Sound Waves (USGS newsletter), cover story.

Pohlman, J., C. Ruppel, C. Maue, L. Brothers, J. Kessler, and C. Worley, 2012, Real-time mapping of seawater and atmospheric methane concentrations offshore of Alaska's North Slope,Sound Waves (USGS newsletter).

Ruppel, C., 2011, Methane hydrates and the future of natural gas, Supplementary Paper #4, The Future of Natural Gas,MIT Energy Initiative study, 25 pp.

Ruppel, C., Collett, T., Boswell, R., Lorenson, T., Buczkowski, B., and W. Waite, 2011. A new global gas hydrate drilling map based on reservoir type, Fire in the Ice, DOE NETL newsletter, May edition, vol. 11(1), 13-17.

Ruppel, C., 2011, USGS Gas hydrates project convenes DOE workshop on climate-gas hydrates interactions,Fire in the Ice, DOE NETL newsletter, May edition, vol. 11(1), 18-20.

Scandella, B. P., C. Varadharajan, H. F. Hemond, C. Ruppel, and R. Juanes, 2011. A conduit dilation model of methane venting from lake sediments,Geophys. Res. Lett., 38, L06408, doi:10.1029/2011GL046768.

Isaksen, I. S. A., M. Gauss, G. Myhre, K. M. Walter Anthony, and C. Ruppel, 2011. Strong atmospheric chemistry feedback to climate warming from Arctic methane emissions, Global Biogeochem. Cycles, 25, GB2002, doi:10.1029/2010GB003845.

Hutchinson, D.R., C. Ruppel, H. Roberts, R. Carney, and M. Smith, 2011, Gas hydrates in the Gulf of Mexico, in: Gulf of Mexico Origin, Waters, and Biota, vol. 3, ed. by N.A. Buster and C.W. Holmes, Texas A&M University Press. ISBN: 978-1603442909.

Santamarina, J.C. and C. Ruppel, 2010, The impact of hydrate saturation on the mechanical, electrical, and thermal properties of hydrate-bearing sand, silts, and clay (Chapter 26), In: Riedel, Willoughby, Chopra (eds), Geophysical Characterization of Gas Hydrates, Society of Exploration Geophysicists Geophysical Developments, vol. 14, 373-384.

Ruppel, C., Hart, P. and C. Worley, 2010, Degradation of subsea permafrost and associated gas hydrate offshore Alaska in response to climate change, Sound Waves, USGS newsletter, October/November edition, cover article.

Lee, J. Y., J. C. Santamarina, and C. Ruppel, 2010a, Parametric study of the physical properties of hydrate-bearing sand, silt, and clay sediments: 1. Electromagnetic properties, J. Geophys. Res., 115, B11104, doi:10.1029/2009JB006669.

Lee, J. Y., F. M. Francisca, J. C. Santamarina, and C. Ruppel, 2010b, Parametric study of the physical properties of hydrate-bearing sand, silt, and clay sediments: 2. Small-strain mechanical properties, J. Geophys. Res., 115, B11105, doi:10.1029/2009JB006670.

Lee, J. Y., J. C. Santamarina, and C. Ruppel, 2010, Volume change associated with formation and dissociation of hydrate in sediment, Geochem. Geophys. Geosyst., 11,, Q03007, doi:10.1029/2009GC002667.

Boswell, R., T. Collett, B. Anderson, and C. Ruppel, 2010, Relative gas volumes for free gas and gas hydrate accumulations, in: DOE NETL newsletter, Fire in the Ice , Summer 2010 edition, pp. 9-11.

Hutchinson, D.R., Hart, P.E., Ruppel, C., Snyder, F., and Dugan, B., 2009, Seismic and thermal characterization of a bottom simulating reflection in the northern Gulf of Mexico, in Collett, T., Johnson, A., Knapp, C., Boswell, R., eds., Natural Gas Hydrates -- Energy Resource Potential and Associated Geologic Hazards, American Association of Petroleum Geologists Memoir 89, 266-286.

Cortes, D. D., A. I. Martin, T. S. Yun, F. M. Francisca, J. C. Santamarina, and C. Ruppel, 2009, Thermal conductivity of hydrate-bearing sediments, J. Geophys. Res., 114,, B11103, doi:10.1029/2008JB006235.

Wooller, M., C. Ruppel, J.W. Pohlman, M.B. Leigh, M. Heintz, and K. Walter Anthony, 2009, Permafrost gas hydrates and climate change: Lake-based seep studies on the Alaskan North Slope, DOE NETL newsletter, Fire in the Ice, , September edition, pp. 7-9.

Ruppel, C., J. Pohlman, and C. Worley, 2009, Studying the link between Arctic methane seeps and degassing methane hydrates, Sound Waves , USGS national newsletter, October edition, cover article.

Ruppel, C., 2009, Methane hydrates and global climate change: a status report, ACS National Meeting, Salt Lake City.

Ruppel, C., Boswell, R., and E. Jones, 2008, Scientific results from Gulf of Mexico Gas Hydrates Joint Industry Project Leg 1 Drilling:  Introduction and overview, Mar. Petr. Geol., 25, doi: 10.1016/j.marpetgeo.2008.02.007.

Pohlman, J. W., C. Ruppel, D. Hutchinson, R.Z. Downer, and R.B. Coffin, 2008, Assessing sulfate reduction and methane cycling in a high salinity pore water system in the Northern Gulf of Mexico, Mar. Petr. Geol., 25, doi: 10.1016/j.marpetgeo.2008.01.016.

Lee, J.Y., J. C. Santamarina, and C. Ruppel, 2008, Mechanical and electromagnetic properties of northern Gulf of Mexico sediments with and without THF hydrate, Mar. Petr. Geol., 25, doi:10.1016/j.marpetgeo.2008.01.019.

Hutchinson, D., Shelander, D., Dai, J., McConnell, D., Shedd, W., Frye, M., Ruppel, C., Boswell, R., Jones, E., Collett, T., Rose, K., Dugan, B., Wood, W., and T. Latham, 2008, Site selection for DOE/JIP gas hydrate drilling in the northern Gulf of Mexico, Proceedings of the 6th  International Conference on Gas Hydrates (ICGH), Vancouver, Canada, 6-10 July, 12 pp.

Jones, E., Latham, T., McConnell, D., Frye, M., Hunt, J., Shedd, W.., Shelander, D., Boswell, R., Rose, K., Ruppel, C., Hutchinson, D., Collett, T., Dugan, B., and W. Wood, 2008, Scientific objectives of the Gulf of Mexico gas hydrate leg II drilling, Proc. Offshore Technology Conference, OTC 19501, 10 pp.

Ruppel, C., and J. Pohlman, January 2008, Climate change and carbon cycle: Perspectives and opportunities, Fire in Ice, DOE/National Energy Technology Lab Gas Hydrates Newsletter, pp. 5-8.

Hornbach, M., L. Lavier, and C. Ruppel, 2007, Triggering mechanism and tsunamogenic potential of the Cape Fear Slide complex, U.S. Atlantic coastal margin, Geochem. Geophys. Geosyst., 8, Q12008 (doi:10.1029/2007GB001722).

**[brief workshop report] Harris, R.N., Fisher, A., Ruppel, C., and Martinez, F., 2008, Modern perspectives on measuring and interpreting seafloor heat flux, EOS Trans. Amer. Geophys. Union, 89(3), p. 23.

Wilson, A., and C. Ruppel, 2007, Salt tectonics and shallow subseafloor fluid convection: Models of coupled fluid-heat-salt transport, Geofluids, 7(4), 377-386. (doi: 10.1111/j.1468-8123.2007.00191.x)

Hornbach, M., C. Ruppel, and C.L. Van Dover, 2007, Three-dimensional structure of fluid conduits sustaining an active deep marine cold seep, Geophysical Research Letters, 34, L05601. (doi: 10.1029/2006GL028859)

Lee, J.Y., T.S. Yun, J.C. Santamarina, and C. Ruppel, 2007, Tetrahydrofuran (THF) as a proxy for methane hydrate in laboratory studies of porous sediments, Geophysics, Geochemistry, Geosystems (G^3), 8,  Q06003. (doi: 10.1029/2006GC001531)

Schultz, G., C. Ruppel, and P. Fulton, 2007, Integrating hydrologic and geophysical data to constrain coastal surficial aquifer processes at multiple spatial and temporal scales, in Subsurface Hydrology: Data Integration for Properties and Processes, ed. by D.W. Hyndman, F.D. Day-Lewis, and K. Singha, American Geophysical Union, Geophysical Monograph Series, 171, pp. 161-182. (doi: 10.1029/171GM13)

Ruppel, C., 2007, Tapping methane hydrates for unconventional natural gas, Elements, 3(3), 193-199.

Yun, T.S., J.C. Santamarina, and C. Ruppel, 2007, Mechanical properties of sand, silt, and clay containing synthetic hydrate, Journal of Geophysical Research, 112, B04106. (doi: 10.1029/2006JB004484)

Heyl, T.P., R.M. Chambers, G.W. Gilchrist, W.P. Gilhooly, S.A. Macko, C. Ruppel, and C.L. Van Dover, 2007, Characteristics of vesicomyid clams and their environment at the Blake Ridge cold seep, Marine Ecology Progress Series, 339, 169-184.

Trehu, A.M., C. Ruppel, J. Dickens, D. Goldberg, M. Holland, M. Riedel, P. Schultheiss, and M. Torres, 2006, Gas hydrates in marine sediments: lessons from ocean drilling, Oceanography, 19, 124-143, 2006.

Yun, T.S., G. Narsilio, J.C. Santamarina, and C. Ruppel, 2006, Instrumented pressure testing chamber for characterizing sediment cores recovered at in situ hydrostatic pressure, Marine Geology, 229, 285-293 (doi: 10.1016/j.margeo.2006.03.012).

Waite, W., C. Ruppel, and S. Kirby, 2006, Comment on Thermal and visual time-series at a seafloor gas hydrate deposit on the Gulf of Mexico slope, Earth and Planetary Science Letters, 245, 481-82. (doi:10.1016/j.epsl.2005.11.062).

Castellini, D.G., G.R. Dickens, G.T. Snyder, and C.D. Ruppel, 2006, Barium cycling in shallow sediment above active mud volcanoes in the Gulf of Mexico, Chemical Geology, 226, 1-30. (doi 10.1016/j.chemgeo.2005.08.008).

Francisca, F., T.S. Yun, C. Ruppel, and J.C. Santamarina, 2005, Geophysical and geotechnical properties of near-surface sediments in the Northern Gulf of Mexico gas hydrate province, Earth and Planetary Science Letters, 237, 924-939. (doi: 10.1016/j.epsl.2005.06.050).

Yun, T.S., F. Francisca, J.C. Santamarina, and C. Ruppel, 2005, Compressional and shear wave velocities of uncemented sediment containing gas hydrate, Geophysical Research Letters, 32, L10609. (doi: 10.1029/2005GL022607)

Ruppel, C., G. Dickens, D.G. Castellini, W. Gilhooly, and D. Lizarralde, 2005, Heat and salt inhibition of gas hydrate in the northern Gulf of Mexico, Geophysical Research Letters, 32, L04625. (doi:10.1029/2004GL021909)

Schultz, G. and C. Ruppel, 2005, Inversion of inductive electromagnetic data in high induction number terrains, Geophysics, 70, G16-G28. (doi:10.1190/1.1852775)

Hornbach, M., C. Ruppel, D. Saffer, C.L. Van Dover, and W.S. Holbrook, 2005, Coupled geophysical constraints on heat flow and fluid flux at a salt diapir, Geophysical Research Letters, 32, L24617. (doi: 10.1029/2005GL024862).

Snyder, M., M. Taillefert, and C. Ruppel, 2004, Redox zonation at the saline-influenced boundaries of a permeable surficial aquifer: effects of physical forcing on the biogeochemical cycling of iron and manganese, Journal of Hydrology, 296, 164-178 (doi: 10.1016/j.jhydrol.2004.03.019.)

Nimblett, J. and C. Ruppel, 2003, Permeability evolution during formation of gas hydrates in marine sediments, Journal of Geophysical Research, 108, 2420, doi: 10.1029/2001JB001650.

Van Dover, C. and others (including Ruppel), 2003, Blake Ridge methane seeps: geological and biological contexts, Deep Sea Research, 50, 281-300.

Ge S, Bekins B, Bredehoeft J, Brown K, Davis EE, Gorelick SM, Henry P, Kooi H, Moench AF, Ruppel C, Sauter M, Screaton E, Swart PK, Tokunaga T, Voss CI, and Whitaker F, 2003, Fluid flow in sub-seafloor processes and future ocean drilling, EOS, 84(16), 151-152.

Salters, V.J.M., P.C. Ragland, W.E. Hames, K. Milla, C. Ruppel, 2002, Temporal chemical variations within lowermost Jurassic tholeiitic magmas of the Central Atlantic magmatic province, in: Central Atlantic Magmatic Province, edited by W.E. Hames, J.G. McHone, P.R. Renne, and C. Ruppel, Geophysical Monograph 136, Washington: AGU, 163-178.

Waite, W.F, deMartin, B.J, Kirby, S.H., Pinkston, J., Ruppel, C.D., 2002, Thermal conductivity measurements in porous mixtures of methane hydrate and quartz sand, Geophysical Research Letters. (doi: 10.1029/2002GL015988)

Ge, S., Bekins, B.A., Bredehoeft, J., Brown, K., Davis, E.E., Gorelick, S.M., Henry, P., Kooi, H., Moench, A.F., Ruppel, C., Sauter, M., Screaton, E., Swart, P.K., Tokunaga, T., Voss, C.I., and Whitaker, F., 2002, Hydrogeology program planning group final report: JOIDES Journal, v. 28, no. 2, p. 24-29.

Schultz, G. and C. Ruppel, 2002, Constraints on hydraulic parameters and implications for groundwater flux across the upland-estuary interface, Journal of Hydrology, 260, , 255-269.

Ruppel, C. and M. Kinoshita, 2000, Heat, fluid, and methane flux on the Costa Rican active margin off the Nicoya Peninsula, Earth and Planetary Science Letters, 179, 153-165.

Salters, V.J.M., P.C. Ragland, W.E. Hames, K. Milla, C. Ruppel, 2002, Temporal chemical variations within lowermost Jurassic tholeiitic magmas of the Central Atlantic magmatic province, in: Central Atlantic Magmatic Province, edited by W.E. Hames, J.G. McHone, P.R. Renne, and C. Ruppel, Geophysical Monograph 136, Washington: AGU, 163-178.

Ruppel, C., Thermal state of the gas hydrate reservoir, 2000, in: Max, M. editor, Natural Gas Hydrate in Oceanic and Permafrost Environments, Kluwer Academic Publishers, 29-42, 2000.

Wood, W. and C. Ruppel, 2000, Seismic and thermal investigations of hydrate bearing sediments on the Blake Ridge Crest: A synthesis of ODP Leg 164 results,Proc. Ocean Drilling Program, Final Reports, 164,253-264.

Xu, W. and C. Ruppel, 1999, Predicting the occurrence, distribution, and evolution of methane gas hydrate in porous marine sediments from analytical models, Journal of Geophysical Research, 104, ,5081-5096.

Ruppel, C., 1997, Anomalously cold temperatures observed at the base of the gas hydrate stability zone, U.S. Atlantic passive margin, Geology, 25, 699-702.

Paull, C., R. Matsumoto et al., 1996, [Ruppel wrote heat flow and physical properties chapters in:] Proceedings of the Ocean Drilling Program, Initial Reports 164.

Ruppel, C., R.P. Von Herzen, and A. Bonneville, 1995, Heat flux through an old (~175 Ma) passive margin: offshore southeastern USA, Journal of Geophysical Research, 100,, 20,037-20,058.

Ruppel, C., 1995, Extensional processes in continental lithosphere [Review paper for AGU's 75th Anniversary], Journal of Geophysical Research, 100, 24,187-24,215.

Schilling, J.-G., C. Ruppel, A.N. Davis, B. McCully, S.A. Tighe, R.H. Kingsley, and J. Lin, 1995, Thermal structure of the mantle beneath the Equatorial Mid-Atlantic Ridge: inferences from the spatial variation of dredge basalt glass compositions, Journal of Geophysical Research, 100, 10,057-10,076.

Hooft, E., M. Kleinrock, and C. Ruppel, 1995, Rifting of oceanic crust at Endeavor Deep on the boundary of the Juan Fernandez microplate, Marine Geophysical Research, 17, 251-273.

Ruppel, C. and K.V. Hodges, 1994, Role of horizontal thermal conduction and finite thrust emplacement in simulation of pressure-temperature-time paths, Earth and Planetary Science Letters, 123, 49-60.

Ruppel, C. and K. Hodges, 1994, Pressure-temperature-time paths from 2D thermal models: prograde, retrograde, and inverted metamorphism, Tectonics, 13, 17-44.

Ruppel, C., M.G. Kogan, and M.K. McNutt, 1993, Implications of two-dimensional gravity data for Baikal Rift zone structure, Geophysical Research Letters, 20, 1639-1642.

A. Bonneville, R.P. Von Herzen, C. Ruppel, 1993, HFSoft: Toolbox for processing marine heat flow data, WHOI Technical Memorandum, 54 pp.

Ruppel, C. and M. McNutt, 1990, Regional isostasy of the Greater Caucasus Mountains from an analysis of Bouguer gravity data, Earth and Planetary Science Letters, 98, p. 360-379.

Ruppel, C., Royden, L., and K. Hodges, 1988, Thermal modelling of extensional tectonics: application to pressure-temperature- time histories of metamorphic rocks, Tectonics, 7, p. 947-957.