Skip to main content

A Gas Hydrate System of Heterogeneous Character in the Nile Deep-Sea Fan

  • Chapter
  • First Online:
World Atlas of Submarine Gas Hydrates in Continental Margins

Abstract

Large deep-sea fans are useful settings to study gas hydrate systems, the rapid burial of organic-rich sediment driving linked processes of gas generation, fluid expulsion and syn-sedimentary tectonism. The Nile deep-sea fan (100,000 km2) is a collapsing Late Cenozoic depocentre that is both a hydrocarbon province and an area of widespread seafloor fluid seepage. Evidence for gas hydrates has been reported in this area, but remains poorly documented. Available seismic and well data are used together with information on seafloor features to characterise a deep-water (1500–2700 m) gas hydrate system in the central Nile fan. The system is in part expressed as a bottom simulating reflection (BSR) discontinuously observed across a relatively small area (6000 km2), both cross-cutting the stratified fill of fault-bound slope basins, and upslope of the basins within thick unstratified mass transport deposits. West of the BSR area, log data from two wells 45 km apart indicate the presence of gas hydrates in intervals up to 75 m thick near the base of the stability zone. Gas hydrates are also likely to be present near the seafloor within hundreds of pockmark-like mounds that record gas venting through the stability zone, most observed west of the BSR area. The central Nile fan thus contains a gas hydrate system expressed as two areas of comparable size, one with a discontinuous BSR but few seafloor gas vents, another lacking a BSR but with downhole evidence of gas hydrates and abundant gas venting. This heterogenous character is suggested to reflect spatial variations in fluid expulsion from the Nile fan, which can inhibit BSR formation while favouring gas hydrate accumulation over wide areas. This possibility has implications for other large deep-sea fans, many of which have restricted BSRs but may contain more extensive gas hydrate systems.

This is a preview of subscription content, log in via an institution to check access.

Access this chapter

Chapter
USD 29.95
Price excludes VAT (USA)
  • Available as PDF
  • Read on any device
  • Instant download
  • Own it forever
eBook
USD 229.00
Price excludes VAT (USA)
  • Available as EPUB and PDF
  • Read on any device
  • Instant download
  • Own it forever
Softcover Book
USD 299.99
Price excludes VAT (USA)
  • Compact, lightweight edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info
Hardcover Book
USD 299.99
Price excludes VAT (USA)
  • Durable hardcover edition
  • Dispatched in 3 to 5 business days
  • Free shipping worldwide - see info

Tax calculation will be finalised at checkout

Purchases are for personal use only

Institutional subscriptions

Similar content being viewed by others

References

Download references

Acknowledgements

D.P. acknowledges funding from the European Union’s Horizon 2020 research and innovation program under Marie Skłodowska-Curie grant agreement no. 656821.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Daniel Praeg .

Editor information

Editors and Affiliations

Rights and permissions

Reprints and permissions

Copyright information

© 2022 Springer Nature Switzerland AG

About this chapter

Check for updates. Verify currency and authenticity via CrossMark

Cite this chapter

Praeg, D., Migeon, S., Mascle, J., Unnithan, V., Ketzer, M. (2022). A Gas Hydrate System of Heterogeneous Character in the Nile Deep-Sea Fan. In: Mienert, J., Berndt, C., Tréhu, A.M., Camerlenghi, A., Liu, CS. (eds) World Atlas of Submarine Gas Hydrates in Continental Margins. Springer, Cham. https://doi.org/10.1007/978-3-030-81186-0_37

Download citation

Publish with us

Policies and ethics