Advertisement

A Petrographic and Geotechnical Study of the Sandstone of the Fundudzi Formation, Lake Fundudzi, South Africa

  • Sibonakaliso G. ChilizaEmail author
  • Egerton D. C. Hingston
Conference paper

Abstract

The Fundudzi Formation is one of five formations of the Soutpansberg Group, which consists essentially of reddish, arenaceous and minor argillaceous deposits. Little is known about the sandstone of the Fundudzi Formation apart from a massive rockslide event that occurred in the Soutpansberg Mountains approximately twenty thousand years ago, which blocked the course of the eastern flowing Mutale River forming Lake Fundudzi, the only true inland lake in South Africa. A study of the petrographic and geotechnical properties of selected samples of sandstones of the Fundudzi Formation has been undertaken in order to contribute to the geotechnical knowledge of this material. Detailed petrographic analysis has been undertaken by analyzing thin sections of selected samples of the sandstone obtained in close proximity to Lake Fundudzi. The geotechnical tests conducted include Schmidt hammer rebound test, point load test, Brazilian strength test and uniaxial compressive strength (UCS) test on representative samples of the sandstone. Based on a detailed petrographic analysis, the sandstone can best be described as quartzitic sandstone. The correlated UCS values derived from Schmidt hammer tests, point load corrected size index strength and UCS values from direct testing of the quartzitic sandstone show that the material classifies as medium to very high strength. The mineralogy, grain size, deformation, grain to grain contact (almost interlocking due to recrystallization) and silica cement were found to significantly affect the strength of Fundudzi Formation sandstone.

Keywords

Lake Fundudzi Petrographic analysis Geotechnical properties Quartzitic sandstone 

Notes

Acknowledgements

Many thanks are also due to Council for Geoscience (CGS) for funding and supporting this project.

References

  1. Allman, M., Lawrence, D.F.: Geological Laboratory Techniques. Blandford, London, pp. 1–335 (1972)Google Scholar
  2. Barker, O.B., Brandl, G., Callahgan, C.C., Eriksson, P.G., van der Neut M.: The Soutpansberg and Waterberg groups and the Blouberg formation. In: Johnson, M.R., Anhaeusser, C.R., Thomas, R.J. (eds.) The Geology of South Africa, Johannesburg/Council for Geosciences, Pretoria, pp. 301–319 (2006)Google Scholar
  3. Bell, F.G.: Engineering Geology, 2nd edn. Butterworth-Heinemann (Elsevier), Burlington, MA. 581 p (2007)Google Scholar
  4. Broch, E., Franklin, J.A.: The point load strength test. Int. J. Rock Mech. Mining Sci. 9(6), 669–697 (1972)Google Scholar
  5. Deere, D.U., Miller, R.P.: Engineering classification and index properties for intact rock. Tech. Rep. No. AFWL-TR-65-115, Air Force Weapons Lab., Kirtland Air Base, New Mexico, pp. 1–332 (1966) Google Scholar
  6. Hoek, E., Bray, J.W.: Rock Slope Engineering, 3rd edn. Institute of Mineralogy and Metallurgy, London, 358 pages (1981)Google Scholar
  7. Hutchison, C.S.: Laboratory Handbook of Petrographic Techniques. Wiley-Interscience, New York, xiii + 527 p (1974)Google Scholar
  8. ISRM: Suggested methods for determining in situ deformability of rock. Int. J. Rock Mech. Min. Sci. Geomech. Abstr. 16(3), 195–214 (1979)Google Scholar
  9. ISRM: Suggested methods for determining hardness and abrasiveness of rocks. In: Brown, E.T. (ed.) Rock Characterization, Testing and Monitoring: ISRM Suggested Methods. Pergamon, Oxford, pp. 95–96 (1981)Google Scholar
  10. ISRM: International society of rock mechanics commission on testing methods, suggested method for determining point load strength. Int. J. Rock Mech. Min. Sci. Geomech. Abstr. 22, 51–60 (1985)Google Scholar
  11. Koncagül, E.C., Santi, P.M.: Predicting the unconfined compressive strength of the Breathitt shale using slake durability, shore hardness and rock structural properties. Int. J. Rock Mech. Min. Sci. 36, 139–153 (1999)CrossRefGoogle Scholar
  12. Miller, R.P.: Engineering classification and index properties for intact rock. Ph.D. thesis, University of Illinois (1965)Google Scholar
  13. van der Waal, B.C.W.: Fundudzi, a unique, sacred and unknown South African Lake. S. Afr. J. Aquat. Sci. 23(1), 42–55 (1997)Google Scholar
  14. Vutukuri, V.S., Lama, R.D., Saluda, S.S.: Mechanical Properties of Rocks, vol. 1. Trans Tech Publications, Switzerland, 280 pages (1974)Google Scholar
  15. Wentworth, C.K.: A scale of grade and class terms for clastic sediments. J. Geol. 30(5), 377–392 (1922)CrossRefGoogle Scholar

Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Sibonakaliso G. Chiliza
    • 1
    Email author
  • Egerton D. C. Hingston
    • 2
  1. 1.Council for GeoscienceSilvertonSouth Africa
  2. 2.College of Agriculture, Engineering and ScienceUniversity of KwaZulu-NatalDurbanSouth Africa

Personalised recommendations