Letter | Published:

Regulation of ice stream flow through subglacial formation of gas hydrates

Nature Geoscience volume 9, pages 370374 (2016) | Download Citation

Abstract

Variations in the flow of ice streams and outlet glaciers are a primary control on ice sheet stability, yet comprehensive understanding of the key processes operating at the ice–bed interface remains elusive. Basal resistance is critical, especially sticky spots—localized zones of high basal traction—for maintaining force balance in an otherwise well-lubricated/high-slip subglacial environment1. Here we consider the influence of subglacial gas-hydrate formation on ice stream dynamics, and its potential to initiate and maintain sticky spots. Geophysical data document the geologic footprint of a major palaeo-ice-stream that drained the Barents Sea–Fennoscandian ice sheet approximately 20,000 years ago. Our results reveal a 250 km2 sticky spot that coincided with subsurface shallow gas accumulations, seafloor fluid expulsion and a fault complex associated with deep hydrocarbon reservoirs. We propose that gas migrating from these reservoirs formed hydrates under high-pressure, low-temperature subglacial conditions. The gas hydrate desiccated, stiffened and thereby strengthened the subglacial sediments, promoting high traction—a sticky spot—that regulated ice stream flow. Deep hydrocarbon reservoirs are common beneath past and contemporary glaciated areas, implying that gas-hydrate regulation of subglacial dynamics could be a widespread phenomenon.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

References

  1. 1.

    In search of ice-stream sticky spots. J. Glaciol. 39, 447–454 (1993).

  2. 2.

    , & Basal mechanics of Ice Stream B, West Antarctica 2. Undrained plastic bed model. J. Geophys. Res. 105, 483–494 (2000).

  3. 3.

    & Stagnation of Ice Stream C, West Antarctica by water piracy. Geophys. Res. Lett. 24, 265–268 (1997).

  4. 4.

    , , & Ice stream sticky spots: a review of their identification and influence beneath contemporary and palaeo-ice-streams. Earth Sci. Rev. 81, 217–249 (2007).

  5. 5.

    , , & A water-piracy hypothesis for the stagnation of Ice Stream C, Antarctica. Ann. Glaciol. 20, 187–194 (1994).

  6. 6.

    , & Response of subglacial sediments to basal freeze-on 2. Application in numerical modeling of the recent stoppage of Ice Stream C, West Antarctica. J. Geophys. Res. 108, 2223 (2003).

  7. 7.

    & Response of subglacial sediments to basal freeze-on 1. Theory and comparison to observations from beneath the West Antarctic ice sheet. J. Geophys. Res. 108, 2222 (2003).

  8. 8.

    et al. Late Quaternary ice sheet history of northern Eurasia. Quat. Sci. Rev. 23, 1229–1271 (2004).

  9. 9.

    , & Submarine landforms and the reconstruction of fast-flowing ice streams within a large Quaternary ice sheet: the 2500-km-long Norwegian-Svalbard margin (57°–80° N). Geol. Soc. Am. Bull. 117, 1033–1050 (2005).

  10. 10.

    , & Formation of mega-scale glacial lineations observed beneath a West Antarctic ice stream. Nature Geosci. 2, 585–588 (2009).

  11. 11.

    & Geomorphological criteria for identifying Pleistocene ice streams. Ann. Glaciol. 28, 67–74 (1999).

  12. 12.

    , , & Ice-sheet dynamics and ice streaming along the coastal parts of northern Norway. Quat. Sci. Rev. 27, 922–940 (2008).

  13. 13.

    , & Ice stream flow-switching during the deglacation of the south-western Barents Sea. Geol. Soc. Am. Bull. 124, 275–290 (2012).

  14. 14.

    , , , & Submarine glacial landforms and rates of ice stream collapse. Geology 36, 819–822 (2008).

  15. 15.

    , & Quaternary geology and deglaciation of the continental shelf off Troms, north Norway. Boreas 8, 217–227 (1979).

  16. 16.

    in Formation and Deformation of Glacial Deposits (eds Warren, C. R. & Croot, D. C.) 95–113 (Balkema, 1994).

  17. 17.

    & Seabed Pockmarks and Seepages: Impact on Geology, Biology and the Marine Environment (Graham and Trotman, 1988).

  18. 18.

    & Clathrate Hydrates of Natural Gases (CRC Press, 2008).

  19. 19.

    et al. Physical properties of hydrate-bearing sediments. Rev. Geophys. 47, RG4003 (2009).

  20. 20.

    , , & Physical properties and rock physics models of sediment containing natural and laboratory-formed methane gas hydrate. Am. Mineral. 89, 1221–1227 (2004).

  21. 21.

    et al. Mechanical behavior of gas-saturated methane hydrate-bearing sediments. J. Geophys. Res. 118, 5185–5194 (2013).

  22. 22.

    , , & The strength and rheology of methane clathrate hydrate. J. Geophys. Res. 108, 2182 (2003).

  23. 23.

    Rheological nonlinearity and flow instability in the deforming bed mechanism of ice stream motion. J. Geophys. Res. 96, 16585–16595 (1991).

  24. 24.

    , & Basal shear stress of the Ross ice streams from control method inversions. J. Geophys. Res. 109, B09405 (2004).

  25. 25.

    , , & Soil investigations, offshore mid Norway: a case study of glacial influence on geotechnical properties. Glob. Planet. Change 12, 271–285 (1996).

  26. 26.

    , & Composition and properties of glacigenic sediments in the southwestern Barents Sea. Mar. Geotechnol. 10, 229–255 (1992).

  27. 27.

    et al. Potential methane reservoirs beneath Antarctica. Nature 488, 633–637 (2012).

  28. 28.

    et al. The global inventory of methane hydrate in marine sediments: a theoretical approach. Energies 5, 2449–2498 (2012).

  29. 29.

    , , , & Air-hydrate crystals in deep ice-core samples from Vostok Station, Antarctica. J. Glaciol. 40, 79–86 (1994).

  30. 30.

    , , , & Pattern and timing of retreat of the last British-Irish ice sheet. Quat. Sci. Rev. 44, 112–146 (2012).

  31. 31.

    , , & Geological History of the Barents Sea (Norges geologiske undersøkelse, 2009).

  32. 32.

    et al. Glacial isostatic adjustment associated with the Barents Sea ice sheet: a modelling inter-comparison. Quat. Sci. Rev. (in the press).

  33. 33.

    et al. Dynamic cycles, ice streams and their impact on the extent, chronology and deglaciation of the British-Irish ice sheet. Quat. Sci. Rev. 28, 758–776 (2009).

Download references

Acknowledgements

This work was partly supported by the Research Council of Norway through its Centres of Excellence funding scheme, project number 223259; the PetroMaks project ‘Glaciations in the Barents Sea area, GlaciBar’ (grant 200672) and the European Commission FP7-People 2012- Initial Training Networks ‘Glaciated North Atlantic Margins, GLANAM’ (grant 317217). We thank the Norwegian Mapping Authority and the Geological Survey of Norway for providing the high-resolution bathymetry data set through the MAREANO programme, TGS for providing the 3D seismic data set and SINTEF Petroleum Research for providing analogue and digital 2D seismic data.

Author information

Affiliations

  1. CAGE—Centre for Arctic Gas Hydrate, Environment and Climate, Department of Geology, UiT The Arctic University of Norway, 9037 Tromsø, Norway

    • Monica Winsborrow
    • , Karin Andreassen
    • , Alun Hubbard
    • , Andreia Plaza-Faverola
    • , Eythor Gudlaugsson
    •  & Henry Patton

Authors

  1. Search for Monica Winsborrow in:

  2. Search for Karin Andreassen in:

  3. Search for Alun Hubbard in:

  4. Search for Andreia Plaza-Faverola in:

  5. Search for Eythor Gudlaugsson in:

  6. Search for Henry Patton in:

Contributions

K.A. developed the study. M.W. interpreted the geophysical data sets and wrote the paper. A.H. contributed to the writing and editing of the paper, advised on its scope and wrote the code for the ice sheet model. H.P. modelled ice thickness and basal temperature. K.A., A.P.-F. and E.G. helped with the interpretation and analysis. M.W. and H.P. prepared the figures. All authors discussed ideas and commented on the paper.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Monica Winsborrow.

Supplementary information

PDF files

  1. 1.

    Supplementary Information

    Supplementary Information

About this article

Publication history

Received

Accepted

Published

DOI

https://doi.org/10.1038/ngeo2696

Further reading