Slope Failures Of The Flanks Of The Southern Cape Verde Islands

  • T. P. Le Bas
  • Douglas G. Masson
  • R. T. Holtom
  • I. Grevemeyer
Part of the Advances in Natural and Technological Hazards Research book series (NTHR, volume 27)

The flanks of the Cape Verde Islands Fogo, Brava and Santiago show extensive evidence of past and potential slope failure. Analyses of bathymetric and subaerial datasets show debris avalanches, turbidite pathways and debris flows, with the transportation of large volumes of rock and sediment. Similarities are seen with many of the processes operating on the flanks of the Canary Islands. In this paper we show the use of different multibeam bathymetry systems for geomorphological description and quantitative analysis. Slope maps, profiles and backscatter analysis can be used to classify the bathymetric characteristics. These derivative processes delineate the size and shape of the debris avalanches and flows and identify channel systems, as well as areas of recent seafloor volcanic activity. Two distinct debris fields covering at least 2000 km2 sourced from the east coast of Fogo are thought to contain up to 250km3 of material. Large slope failures, such as those from Fogo, may result in damage to seafloor installations such as submarine cables. However, greater hazards may be posed by the consequent generation of tsunamis.

Keywords

Transportation Radar Turbidity Holocene Lithosphere 

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References

  1. Ali, M.Y., Watts, A.B., & Hill, I., 2003, A seismic reflection profile study of lithosphere flexure in the vicinity of the Cape Verde Islands: Journal of Geophysical Research, v. 108 (B5), 24pp.CrossRefGoogle Scholar
  2. Dash, B.P., Ball, M.M., King, G.A., Butler, L.W., & Rona, P.A., 1976, Geophysical investigation of the Cape Verde Archipelago: Journal of Geophysical Research, v. 81 (29|), p. 5249–5259.CrossRefGoogle Scholar
  3. Day, S.J., Heleno da Silva, S.I.N., & Fonseca, J.F.B.D., 1999, A past giant lateral collapse and present-day flank instability of Fogo, Cape Verde Islands: Journal of Volcanology and Geothermal Research, v. 94, p. 191–218.CrossRefGoogle Scholar
  4. Detrick, R.S., & Crough, S.T., 1978, Island subsidence, Hot spots, and Lithospheric thinning: Journal of Geophysical Research, v. 83 (B3), p. 1236–1244.CrossRefGoogle Scholar
  5. Hampton, M.A., Lee, H.J., & Locat, J., 1996, Submarine landslides: Reviews of Geophysics, v. 34, p. 33–59.CrossRefGoogle Scholar
  6. Heleno da Silva, S.I.N., Faria, B., Bandamo, Z., & Fonseca, J., 2005, Observations of high-frequency harmonic tremor in Fogo Island, Cape Verde. SAL2005 Workshop on Ocean Island Volcanism, Abstract volume p. 61.Google Scholar
  7. Holocomb, R.T., & Searle, R.C., 1991, Large landslides from oceanic volcanoes: Marine Geotechnology, v. 10, p. 19–32.CrossRefGoogle Scholar
  8. Holm, P.M., Wilson, J.R., Christensen, B.P., Hansen, L., Hansen, S.L., Hein, K.M., Mortensen, A.K., Pedeersen, R., Plesner, S., & Runge, M.K., 2006, Sampling the Cape Verde Mantle Plume: Evolution of Melt Compositions on Santo Antão, Cape Verde Islands: Journal of Petrology, v. 47 (1), p. 145–189.Google Scholar
  9. Le Bas T.P., 2005, PRISM - Processing of Remotely-sensed Imagery for Seafloor Mapping - Version 4.0. National Oceanography Centre Southampton report. Unpublished manuscript. 192pp.Google Scholar
  10. Masson, D.G., 1996, Catastrophic collapse of the flank of El Hierro about 15,000 years ago, and the history of large flank collapses in the Canary Islands: Geology, v. 25, p. 231–234.CrossRefGoogle Scholar
  11. Masson, D.G., Watts, A.B., Gee, M.J.R., Urgeles, R., Mitchell, N.C., LeBas, T.P., & Canals, M., 2002, Slope failures on the flanks of the western Canary Islands: Earth-Science Reviews, v. 57, p. 1–35.CrossRefGoogle Scholar
  12. McNutt, M., 1988, Thermal and Mechanical Properties of the Cape Verde Rise: Journal of Geophysical Research, v. 93, p. 2784–2794.CrossRefGoogle Scholar
  13. Mitchell, J.G., Le Bas, M.J., Zielonka, J., & Furnes, H., 1983, On the magmatism on Maio, Cape Verde Islands: Earth and Planetary Science Letters, v. 64, p. 61–76.CrossRefGoogle Scholar
  14. Mitchell, N.C., Masson, D.G., Watts, A.B., Gee, M.J.R., & Urgeles, R., 2002, The morphology of the submarine flanks of volcanic islands. A comparative study of the Canary and Hawaiian hotspot islands: Journal of Volcanology and Geothermal Research, v. 115, p. 83–107.CrossRefGoogle Scholar
  15. Moore, J.G., Clague, D.A., Holcomb, R.T., Lipman, P.W., Normark, W.R., & Torresan, M.E., 1989, Prodigious submarine landslides on the Hawaiian Ridge: Journal of Geophysical Research, v. 94, (B12), p. 17465–17484.CrossRefGoogle Scholar
  16. Moore, J.G., Normark, W.R., & Holcomb, R.T., 1994, Giant Hawaiian Landslides: Annual Review of Earth Planetary Science, v. 22, p. 119–144.CrossRefGoogle Scholar
  17. Oehler, J-K., Labazuy, P., & Lénat, J-F., 2004, Recurrence of major flank landslide during the last 2-Ma history of Reunion Island: Bulletin of Volcanology, v. 66, p. 585–598.CrossRefGoogle Scholar
  18. Rabus, B., Eineder, Roth, A., & Bamler, R., 2003, The shuttle radar topography mission- a new class of digital elevation models acquired by spaceborne radar: Photogrammetry Remote Sensing, v. 57, p. 241–262.CrossRefGoogle Scholar
  19. Torres, P.C., Madeira, J., Silva, L.C., Brum da Silveira, A., Serralheiro, A., & Mota Gomes, A., 1998, Carta Geologica da Ilha do Fogo (Republica de Cabo Verde): Lisbon, Departmento de Geologia da Faculdade de Ciencas da Universidade de Lisboa.Google Scholar
  20. Ward, S. N. & Day, S. J. 2001. Cumbre Vieja volcano - potential collapse and tsunami at La Palma, Canary Islands. Geophysical Research Letters 28, 3397–3400.CrossRefGoogle Scholar
  21. Watts, A.B. & Masson, D.G. 1995. A giant landslide on the north flank of Tenerife, Canary Islands. Journal of Geophysical Research 100(B12) pp 24487–24498.CrossRefGoogle Scholar
  22. Wynn, R.B. & Masson, D.G., 2003, Canary Islands landslides and tsunami generation: Can we use turbidite deposits to interpret landslide processes?, p. 325-332. In: Submarine mass movements and their consequences. J. Locat and J. Mienert Eds., Advances in Natural and Technological Hazards Research Series, 2003, Kluwer.Google Scholar

Copyright information

© Springer 2007

Authors and Affiliations

  • T. P. Le Bas
    • 1
  • Douglas G. Masson
    • 1
  • R. T. Holtom
    • 1
  • I. Grevemeyer
    • 2
  1. 1.National Oceanography CentreUK
  2. 2.Leibniz-Institute of Marine SciencesIFM-GEOMARGermany

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