Abstract
Submarine landslides are very common on the tectonically and seismically active Ligurian margin, NW-Mediterranean Sea. We present geophysical, sedimentological and geotechnical results from two extensive landslide complexes in water depth exceeding 1,500 m on the steep continental slope (>11°) near the Var Canyon. At the Western Landslide Complex, facing the Var Canyon, we observe multiple headwalls and tilted layering. Undisturbed and failed sediments are characterised by a downward increase in bulk density and shear strength, the failed portion of which shows low intrinsic friction coefficients of 0.27. Otherwise, at the Eastern Landslide Complex, which shows smooth headwall features containing debrites and hemipelagic silty clays with pebbles, we observed constant bulk density of the failed sediments; however the shear strength in the remobilized sediment is lower than in the hemipelagites. This indicates that the failed material may have incorporated seawater and has retained its underconsolidated state until the present. The material is hence prone to future landsliding in case of seismic loading and/or the occurrence of other factors destabilizing the sediment.
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Bartetzko A, Kopf A (2007) The relationship of undrained shear strength and porosity with depth in shallow (< 50 m) marine sediments. Sediment Geol 196: 235–249.
Bethoux N, Ouillon G, Nicolas M (1998) The instrumental seismicity of the western Alps: spatio-temporal patterns analysed with the wavelet transform. Geophys J Int 135: 177–194.
Blum P (1997) Physical properties handbook: a guide to the shipboard measurement of physical properties of deep-sea cores. Technical Note 26, ODP, doi:10.2973/odp.tn.26.1997.
Bryn P, Berg K, Forsberg CF, Solheim A, Kvalstad TJ (2005) Explaining the Storegga Slide. Mar Petrol Geol 22: 11–19.
Burrus J, Bessis F, Doligez B (1987) Heat flow, subsidence and crustal structure of the Gulf of Lion (NW Mediterranean): A quantitative discussion of the classical passive margin model. In: Beaumont C, Tankard AJ (Eds.) Sedimentary Basins and Basin-Forming Mechanisms. AGS Spec Publ 5, Mem Can Soc Pet Geol 12: 1–15, Halifax.
Casagrande A (1936) The Determination of the Pre-consolidation Load and its Practical Significance. Proc Int Conf SMFE 3: 60–64.
Cochonat P, Bourillet JF, Savoye B, Dodd L (1993) Geotechnical characteristics and instability of submarine slope sediments, the Nice slope (N-W Mediterranean Sea). Mar Georesourc Geotech 11: 131–151.
Dan G, Sultan N, Savoye B (2007) The 1979 Nice harbour catastrophe revisited: Trigger mechanism inferred from geotechnical measurements and numerical modelling. Mar Geol 245: 40–64.
Densmore AL, Anderson RS, McAdoo BG, Ellis MA (1997) Hillslope evolution by Bedrock landslides. Sciences 275: 369–372.
Dugan B, Flemings PB (2000) Overpressure and fluid flow in the New Jersey continental slope: implications of slope failure and cold seeps. Sciences 289: 288–291.
Hampton MA, Lee HJ, Locat J (1996) Submarine landslides. Rev Geophys 3: 33–59.
Klaucke I, Cochonat P (1999) Analysis of past seafloor failures on the continental slope off Nice (SE France). Geo-Mar Lett 19: 245–253.
Klaucke I, Savoye B, Cochonat P (2000) Patterns and processes of sediment dispersal on the continental slope off Nice, SE France. Mar Geol 162: 405–422.
Kopf A, Brown KM (2003) Friction experiments on saturated sediments and their implications for the stress state of the Nankai and Barbados subduction thrusts. Mar Geol 202: 193–210.
Kopf A, Cruise Participants (2008) Report and Preliminary Results of Meteor Cruise M 73/1: LIMA-LAMO (Ligurian Margin Landslide Measurements & Observatory), Cadiz, 22.07.2007– Genoa, 11.08.2007. Berichte Fachbereich Geowissenschaften, Universität Bremen, 264.
Locat J, Lee HJ (2002) Submarine landslides: advances and challenges. Can Geotech J 39: 193–212.
McAdoo BG, Pratson LF, Orange DL (2000) Submarine landslide geomorphology, US continental slope. Mar Geol 169: 103–136.
Migeon S, Mulder T, Savoye B, Sage F (2006) The Var turbidite system (Ligurian Sea, northwestern Mediterranean) — morphology, sediment supply, construction of turbidite levee and sediment waves: implications for hydrocarbon reservoirs. Geo-Mar Lett 26: 361–371.
Mulder T, Tisot JP, Cochonat P, Bourillet JF (1994) Regional assessment of mass failure events in the baie des Anges, Mediterranean Sea. Mar Geol 122: 29–45.
Mulder T, Savoye B, Syvitski JPM, Piper DJW (1998) The Var Submarine System: understanding Holocene sediment delivery processes and their importance to the geological record. In: Stoker MS, Evans D, Cramp A (Eds.) Geological Processes on Continental Margins: Sedimentation, Mass Wasting and Stability. Spec Publ Geol Soc Lond 129, Ocean Drilling Program, College Station, TX, pp. 145–166.
Pasquale V, Verdoya M, Chiozzi P (1996) Heat flux and timing of the drifting stage in the Ligurian-Provencal basin (Northwestern Mediterranean). J Geodyn 21: 205–222.
Piper DJW, Savoye B (1993) Processes of late Quaternary turbidity current flow and deposition on the Var deep-sea.fan, northwest Mediterranean Sea. Sedimentol 40: 557–582.
Postma G, Nemec W, Kleinspehn KL (1988) Large floating clasts in turbidites: a mechanism for their emplacement. Sed Geol 58: 47–61.
Rehault JP, Bethoux N (1984) Earthquake relocation in the Ligurian Sea (Western Mediterranean): geological interpretation. Mar Geol 55: 429–445.
Ryan, WBF (2009) Decoding the Mediterranean salinity crisis. Sedimentol 56: 95–136.
Sultan N, Cochonat P, Dennielou B, Bourillet JF, Savoye B, Colliat JL (2000) Surconsolidation apparente et pression osmotique dans un sédiment marin. C R Acad Sci Paris – Ear Planet Sci 331: 379–386.
Sultan N, Cochonat P, Canals M, Cattaneo A, Dennielou B, Haflidason H, Laberg, JS, Long D, Mienert J, Trincardi F, Urgeles R (2004) Triggering mechanisms of slope instability processes and sediment failures on continental margins: a geotechnical approach. Mar Geol 213: 291–321.
Wood DM (1982) Cone penetrometer and liquid limit. Géotechnique 32: 152–157.
Acknowledgments
We thank the captain and crew of the RV Meteor for their support during the cruise M73/1. IFREMER Brest (France) is acknowledged for having provided the bathymetric map. We also thank the reviewers Angelo Camerlenghi and Brian McAdoo for their efforts and suggestions to improve the manuscript. This study was financed through the Deutsche Forschungsgemeinschaft (RCOM-MARUM, Project C8/D3) and supported by the DFG-Excellence Initiative International Graduate School for Marine Sciences, Bremen.
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Förster, A., Spieβ, V., Kopf, A., Dennielou, B. (2010). Mass Wasting Dynamics at the Deeper Slope of the Ligurian Margin (Southern France). In: Mosher, D.C., et al. Submarine Mass Movements and Their Consequences. Advances in Natural and Technological Hazards Research, vol 28. Springer, Dordrecht. https://doi.org/10.1007/978-90-481-3071-9_6
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DOI: https://doi.org/10.1007/978-90-481-3071-9_6
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