Authors: Oldcorn, RC; Seago, RD


Cite As:
Oldcorn, RC & Seago, RD 2007, 'Understanding the Bigger Picture - Interpretation of Geological Structure in Open Pit Rock Slope Stability', in Y Potvin (ed.), Slope Stability 2007: Proceedings of the 2007 International Symposium on Rock Slope Stability in Open Pit Mining and Civil Engineering, Australian Centre for Geomechanics, Perth, pp. 449-462,

Download citation as:   ris   bibtex   endnote   text   Zotero

Expert assessment of geological structure can significantly improve understanding of the open pit geotechnical framework. A good structural model of the pit and surroundings is essential to understand the potential for slope instability, though commonly only the local area is generally assessed. This can lead to major features or deformation styles being missed. This paper demonstrates how structural evaluation has been used to improve the geological and geotechnical understanding of the pit slope stability issues at two very different sites. The Kumtor open pit gold mine is located in the tectonically complex Tien Shan Mountains in Kyrgyzstan. The structural geology is being reassessed, since it was proving difficult to understand styles of deformation and hence predict what potential failures could develop as the pit expanded. Careful assessment of in-pit and wider data has resulted in development of a comprehensive picture of the structural geology, from a regional to pit scale, including interpretation of the structure to be expected in the final slopes. Work is continuing to develop this interpretation, for long term mine planning purposes. Taffs Well Quarry is located within Carboniferous Limestone of the South Wales syncline. A re-evaluation of the geological structure was carried out, as a failure indicated changes in structural style not previously expected. Structural mapping identified thrust faulting associated with major folding. These faults could potentially lead to significant failures as the quarry was expanded. The model was used to predict the structural scenario in the final quarry profile and allowed geotechnical design to be more confidently carried out.

Abeleira, A., Ansdell, K.M., Thomas, D., Heaman, L. and Melrose, D.L. (2000) Geology and Structural Evolution of
the Kumtor Region, Tien Shan, Kyrgyzstan. In Bucci L.A. and Mair J.L (editors), 2000. Gold in 2000. Poster
session, extended abstracts, Lake Tahoe, Nevada, Nov. 10-11, 2000, pp. 41-52.
Centerra Gold Inc. (2006) Technical Update Report on the Kumtor Gold Mine Kyrgyz Republic for Centerra Gold Inc.
and Cameco Corporation. Strathcona Mineral Services Limited.
Pringle, J. and George, T.N. (1948) British Regional Geology, South Wales. Second Edition. HMSO.
Squirrel, H.C. and Downing, R.A. (1968) Geology of the South Wales Coalfield. Memoirs of the Geological Survey of
Great Britain, HMSO, p. 333.
Thomas, D. (1999) A review of the geological setting of the 3900 block area, Kumtor gold deposit, Kyrgyzstan. KOC
Internal Report.
Wyllie, D.C. and Mah, C.W. (2004) Rock Slope Engineering, Civil and Mining. Spon Press.
Zonenshain, L.P., Kuzmin, M.I. and Natapov, L.M. (1990) Geology of the USSR: A plate tectonic synthesis, AGU
Geodynamics Series, Vol. 21, Washington D.C.
Understanding the Bigger Picture — Interpretation of Geological Structure in
Open Pit Rock Slope Stability R.C. Oldcorn, R.D. Seago
462 Slope Stability 2007, Perth, Australia

© Copyright 2023, Australian Centre for Geomechanics (ACG), The University of Western Australia. All rights reserved.
Please direct any queries or error reports to