Abstract
Overpressure generation due to rapid sediment deposition can result in low effective stresses within the sediment column. It has been proposed that these large overpressures are the main preconditioning factor for causing large-scale submarine slope failure on passive continental margins, such as those in the Gulf of Mexico and offshore Norway. The rate of overpressure generation depends on the sedimentation rate, sediment compressibility and permeability. The Gulf of Mexico and the Norwegian continental slope have experienced comparatively high sediment input, but large-scale slope failure also occurs in locations with very low sedimentation rates such as the Northwest African continental margin. Here we show results from 2D numerical modelling of a 2° continental slope subjected to deposition rates of 0.15 m/ka. These results do not indicate any evidence for significant overpressure or slope instability. We conclude that factors other than overpressure must be fundamental for initiating slope failure, at least in locations with low sedimentation rates.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Antobreh AA, Krastel S (2007) Mauritania slide complex: morphology, seismic characterisation and process of formation. Int J Earth Sci 96:451–472
Bouriak S, Vanneste M, Saoutkine A (2000) Inferred gas hydrates and clay diapirs near the Storegga slide on the southern edge of the Voring plateau, offshore Norway. Mar Geol 163:125–148
Bull S, Cartwright J, Huuse M (2009) A subsurface evacuation model for submarine slope failure. Basin Res 21:433–443
Davies RJ, Clarke AL (2010) Methane recycling between hydrate and critically pressured stratigraphic traps, offshore Mauritania. Geology 38:963–966
Demars KR (1982) Unique engineering properties and compression behavior of deep-sea calcareous sediments. In: Demars KR, Chaney RC (eds) Geotechnical properties, behavior and performance of calcareous soils. ASTM, Philadelphia
Flemings PB, Long H, Dugan B, Germaine JT, John CM, Behrmann JH, Sawyer DE et al (2008) Erratum to “pore pressure penetrometers document high overpressure near the seafloor where multiple sub- marine landslides have occurred on the continental slope, offshore Louisiana, Gulf of Mexico”. Earth Planet Sci Lett 274:269–283
Gibson RE (1958) The progress of consolidation in a clay layer increasing in thickness with time. Geotech 8(2):171–182
Haflidason H, Lien R, Sejrup HP, Forsberg CF, Bryn P (2005) The dating and morphometry of the Storegga slide. Mar Petrol Geol 22:123–136
Hamilton EL (1976) Variations of density and porosity with depth in deep-sea sediments. J Sediment Petrol 46(2):280–300
Henrich R, Hanebuth TJJ, Krastel S, Neubert N, Wynn RB (2008) Architecture and sediment dynamics of the Mauritania slide complex. Mar Petrol Geol 25(1):17–33
Karig DE, Hou G (1992) High-stress consolidation experiments and their geological implications. J Geophys Res 97(B1):289–300
Kawamura K, Ogawa Y (2004) Progressive change of pelagic clay microstructure during burial process: examples from piston cores and ODP cores. Mar Geol 207:131–144
Krastel S, Wynn RB, Geersen J, Henrich R, Georgiopoulou A, Meyer M, Schwenk T (2012) Large scale mass wasting at the NW-African continental margin: some general implications for mass wasting at passive continental margins. In: Yamada Y et al (eds) Submarine mass movements and their consequences, vol. 31, Advances in natural and technological hazards research. Springer, Dordrecht, pp 189–199
Leynaud D, Sultan N, Mienert J (2007) The role of sedimentation rate and permeability in the slope stability of the formerly glaciated Norwegian continental margin: the Storegga slide model. Landslides 4:297–309
Potts DM, Zdravkovic L (2001) Finite element analysis in geotechnical engineering: theory. Thomas Telford, London
Roscoe KH, Burland JB (1968) On the generalised stress-strain behaviour of ‘wet’ clay. In: Engineering plasticity. Cambridge University Press, Cambridge, pp 535–609
Ruddiman WF, Sarnthein M et al (1988) In: Proceedings of the ODP 108, ODP initial reports, College station
Sager WW, Lee CS, Macdonald IR, Schroeder WW (1999) High- frequency near-bottom acoustic reflection signatures of hydrocarbon seeps on the northern Gulf of Mexico continental slope. Geo-Mar Lett 18:267–276
Sarnthein M, Thiede J, Pflaumann U, Erlenkeuser U, Fütterer D (1982) Atmospheric and oceanic circulation patterns off Northwest Africa during the past 25 million years. In: von Rad U (ed) Geology of the Northwest African continental margin. Springer, Berlin, pp 545–604
Stigall J, Dugan B (2010) Overpressure and earthquake initiated slope failure in the Ursa region, northern Gulf of Mexico. J Geophys Res 115(B4):B04101
Twichell DC, Chaytor JD, ten Brink US, Buczkowski B (2009) Morphology of late quaternary submarine landslides along the U.S. Atlantic continental margin. Mar Geol 264:4–15
Valent PJ, Altschaeffl AG, Lee HJ (1982) Geotechnical properties of two calcareous oozes. In: Demars KR, Chaney RC (eds) Geotechnical properties, behavior and performance of calcareous soils. ASTM, Philadelphia
Velde B (1996) Compaction trends of clay-rich deep sea sediments. Mar Geol 133:193–201
Wynn RB, Masson DG, Stow DAV, Weaver PPE (2000) The northwest African slope apron: a modern analogue for deep-water systems with complex seafloor topography. Mar Petrol Geol 17:253–265
Yang Y, Aplin AC (2010) A permeability-porosity relationship for mudstones. Mar Petrol Geol 27:1692–1697
Acknowledgments
Sebastian Krastel kindly provided reflection seismic lines offshore NW Africa. Brandon Dugan, Peter Flemings and Derek Sawyer are thanked for their encouragement to address these problems. We also thank the reviewers C. Berndt and A. Kopf for their constructive reviews.
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2012 Springer Science+Business Media B.V.
About this paper
Cite this paper
Urlaub, M., Zervos, A., Talling, P.J., Masson, D.G., Clayton, C.I. (2012). How Do ∼2° Slopes Fail in Areas of Slow Sedimentation? A Sensitivity Study on the Influence of Accumulation Rate and Permeability on Submarine Slope Stability. In: Yamada, Y., et al. Submarine Mass Movements and Their Consequences. Advances in Natural and Technological Hazards Research, vol 31. Springer, Dordrecht. https://doi.org/10.1007/978-94-007-2162-3_25
Download citation
DOI: https://doi.org/10.1007/978-94-007-2162-3_25
Published:
Publisher Name: Springer, Dordrecht
Print ISBN: 978-94-007-2161-6
Online ISBN: 978-94-007-2162-3
eBook Packages: Earth and Environmental ScienceEarth and Environmental Science (R0)