Slope evolution and slope stability, Kawarau valley, Central Otago, New Zealand

  • Bell D. H. 
Section 13 Engineering Geology


Slopes developed within the Kawarau Valley in response to Late Pleistocene fluvial, glacial and periglacial processes, with localised slope failures continuing during Holocene times. Rock mass anisotropy within the basement chlorite schists has been a major influence in geomorphic development, and extensive mass movement deposits now mantle the valley slopes. A chronology of events is presented, based in part on radiocarbon dating and pollen analysis, and geological and geotechnical aspects of slope instability are reviewed with reference to particular landslide areas. Slope evolution within the Kawarau Valley has major engineering and environmental implications, and these are discussed in relation to proposed hydro-electric development, roading and land use. Quantitative assessment of the stability of both rock and soil slopes must take account of the complex geological controls of slope development, and investigation methods are outlined.


Mass Movement Slope Failure Rock Slope Landslide Area Wedge Failure 

Évolution Des Pentes Et Stabilite Des Pentes, Vallée Du Kawarau, Otago Central, Nouvelle-Zéalande


Dans la vallée du Kawarau, à la fin du Pléistocène, des processus fluviatiles, glaciaires et périglaciaires ont abouti à la formation de pentes qui présentent des ruptures localisées d’âge holocène. L’anisotropie du massif rocheux dans les chloritoschistes de base a eu une influence primordiale sur la formation du modelé, et actuellement, les pentes de la vallée sont recouvertes par de vastes dépôts dûs à des mouvements de masses. On présente la chronologie des événements, basée d’une part sur la datation au radiocarbone et d’autre part sur l’étude palynologique; puis les aspects géologiques et géotechniques de l’instabilité des pentes sont passés en revue, avec référence à des régions particulières où des glissements de terrain on été observés. L’évolution des pentes dans la vallée du Kawarau a des implications importantes pour les constructions et pour l’environnement: elles sont discutées à propose de projets hydroélectriques, routiers et d’utilisation du sol. Des évaluations quantitatives de la stabilité des roches et des sols en pente doivent tenir compte des facteurs géologiques complexes qui ont formé ces pentes; on donne une esquisse des méthodes d’investigation.


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  1. 1.
    BELL D.H. — MULLER E.H. (In preparation): Geomorphic History of the Kawarau Valley, Central Otago, New Zealand: Part I — Pre-Glacial Origins.Google Scholar
  2. 2.
    BELL D.H. — MULLER E.H. (In preparation): Ibid: Part II — Late Pleistocene Glacial Geology.Google Scholar
  3. 3.
    de FREITAS M. H. — WATTERS R.J. (1973): Some Field Examples of Toppling Failure. Géotechnique 23, 495–514.CrossRefGoogle Scholar
  4. 4.
    EMBLETON C. — KING C.A.M. (1975): Periglacial Geomorphology. Edward Arnold, London, 203 p.Google Scholar
  5. 5.
    FRANKLIN J.A. — DENTON P.E. (1973): The Monitoring of Rock Slopes. Q. Jl. Engng. Geol. 6, 259–87.CrossRefGoogle Scholar
  6. 6.
    GAGE M. (1965): Some Characteristics of Pleistocene Cold Climates in New Zealand. Trans. Roy. Soc. N.Z. 3(2), 11–21.Google Scholar
  7. 7.
    HIGGINBOTTOM I.E. — FOOKES P.G. (1971): Engineering Aspects of Periglacial Features in Britain. Q. Jl. Engng. Geol. 3, 85–117.CrossRefGoogle Scholar
  8. 8.
    HOEK E. — BRAY J.W. (1973): Rock Slope Engineering. Inst. of Mining and Metallurgy, London, 309 p.Google Scholar
  9. 9.
    HOEK E. — BRAY J.W. — BOYD J.M. (1973): The Stability of a Rock Slope containing a Wedge resting on Two Intersecting Discontinuities. Q. Jl. Engng. Geol. 6, 1–55.CrossRefGoogle Scholar
  10. 10.
    HUTCHINSON J.N. (1968): Mass Movement. In: Encyclopaedia of Geomorphology, Fairbridge F.W. (ed.), Reinhold Book Corp., New York, 688–95.CrossRefGoogle Scholar
  11. 11.
    LEAMY M.L. (1972): Finge-Textured Dissection in Semi-Arid Central Otago. N.Z. Jl. Geol. Geophys. 15(3), 394–405.CrossRefGoogle Scholar
  12. 12.
    LEAMY M.L. (1973): Subsoil Claypans as Quaternary Markers in Semi-Arid Central Otago. N.Z. Jl. Geol. Geophys. 16(3), 611–22.CrossRefGoogle Scholar
  13. 13.
    LEAMY M.L. — BURKE A.S. (1973): Identification and Significance of Paleosols in Cover Deposits in Central Otago. N.Z. Jl. Geol. Geophys. 16(3), 623–35.CrossRefGoogle Scholar
  14. 14.
    MARTIN G.R. — MILLAR P.J. (1974): Stability of Slopes in Weathered and Jointed Rock. N.Z. Inst. Engrs. Proc. Techn. Groups Vol. 1 Issue 5(G), 7.1–7.13.Google Scholar
  15. 15.
    McCRAW J.D. (1965): Landscapes in Central Otago. In LISTER R.G. — HARGREAVES R.P. (eds.) Central Otago. N.Z. Geogr. Soc. Misc. Ser. 5, Caxton Press, Christchurch, 30–45.Google Scholar
  16. 16.
    McKELLAR I.C. (1960): Pleistocene Deposits of the Upper Clutha Valley, Central Otago, New Zealand. N.Z. Jl. Geol. Geophys. 3, 432–60.Google Scholar
  17. 17.
    McKELLAR I.C. — BROWN I.R. (1975): The Fall of Nevis Bluff. Abstracts, Geol. Soc. N.Z. Inc. Annual Conference, Kaikoura, Nov. 1975.Google Scholar
  18. 18.
    MITCHELL M.T. (1974): The Use of Instrumentation in Evaluating the Stability of Natural Slopes. N.Z. Inst. Engrs. Proc. Tech. Groups Vol. 1 Issue 5(G), 6.31–6.46Google Scholar
  19. 19.
    RILEY P.B. (1974): Stability of Hard Rock Slopes. Ibid, 7.15–7.21.Google Scholar
  20. 20.
    SOONS J.M. (1962): A Survey of Periglacial Features in New Zealand. In: Land and Livelihood/ Geographical Essays in Honour of George Jobberns, M. McCaskill (ed.), N.Z. Geogr. Soc., Christchurch, 74–87.Google Scholar
  21. 21.
    SUGGATE R.P. (1965): Late Pleistocene Geology of the Northern Part of the South Island, New Zealand. N.Z. Geol. Surv. Bull. 77, 91 p.Google Scholar
  22. 22.
    TERZAGHI K. — PECK R.B. (1967): Soil Mechanics in Engineering Practice. 2nd ed., John Wiley and Sons, New York, 729 p.Google Scholar
  23. 23.
    TOURTELOT H.A. (1974): Geologic Origin and Distribution of Swelling Clays. Bull. Ass. Engng. Geol. XI(4), 259–275.Google Scholar
  24. 24.
    TURNBULL I.M. — BARRY J.M. — CARTER R.M. — NORRIS R.J. (1975): The Bobs Cove Beds and their Relationship to the Moonlight Fault Zone. J. Roy. Soc. N.Z. 5(4), 355–94.CrossRefGoogle Scholar
  25. 25.
    WAHLSTROM E.E. (1974): Dams, Dam Foundations and Reservoir Sites. Elsevier, New York, 278 p.Google Scholar
  26. 26.
    WELLS J.A. (1972): Ecology of Podocarpus hallii in Central Otago, New Zealand. N.Z. Jl. Bot. 10(3), 399–426.CrossRefGoogle Scholar
  27. 27.
    WILLETT R.W. (1950): The New Zealand Pleistocene Snow Line, Climatic Conditions, and Suggested Biological Effects. N.Z. Jl. Sci. Technol. 32B(1), 18–48.Google Scholar
  28. 28.
    WOOD B.L. (1962): Sheet 22 — Wakatipu. Geological Map of New Zealand 1 : 250,000, N.Z. Dept. Sci. Ind. Res., Wellington.Google Scholar
  29. 29.
    WOOD B.L. (1963): Structure of the Otago Schists, N.Z. Jl. Geol. Geophys. 6;641–80.CrossRefGoogle Scholar
  30. 30.
    WOOD B.L. (1969): Periglacial Tor Topography in Southern New Zealand. N.Z. Jl. Geol. Geophys. 12, 361–75.CrossRefGoogle Scholar

Copyright information

© International Association of Engineering Geology 1976

Authors and Affiliations

  • Bell D. H. 
    • 1
  1. 1.Geology DepartmentUniversity of CanterburyChristchurchNew Zealand

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