ANALYSES OF ROCK SURFACE COLOUR CHANGES DUE TO WEATHERING

Mehmet Kemal GÖKAY

ANALYSES OF ROCK SURFACE COLOUR CHANGES DUE TO WEATHERING

Mehmet Kemal GÖKAY

Öz

Description parameters of rock masses and minerals include their colours as well. Colours appear in daylight for surfaced rock masses are changing slightly due to weathering layers which have been covering its surface gradually. Healthy human eyes can manage to differentiate visible spectrum to identify the colours of substance including rock masses. Then visible blackish colours of magnetite minerals, reddish colours of Terra- Rosa soils, greenish colours of weathered copper ore, pure white of salt minerals and many others are differentiable by naked eyes. Different colours and homogeneity of colour distribution for natural rocks are also main grading parameters of natural rock surfaces. In addition, colour can also be parameter to identify weathered rock surfaces. Outcrop rock mass surfaces or rock discontinuity surfaces which could be influenced by outside factors, mainly water, and their colours are differentiated. In this study, colour changes were determined in digital manner by obtaining rock surfaces’ Red, Green, Blue digital colour (RGB) values. Digital colour differences have been then analyzed more specifically to evaluate rock weathering and colour changes.

Anahtar Kelimeler

Decolourisation, Rock weathering, Colour change, Color analyses.

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Referanslar

Annerel, E. and Taerwe, L., 2011, “Methods to quantify the colour development of concrete exposed to fire”, Construction and Building Materials. 25, 10, 3989-3997.

Anon, 1970, “Using a remotely controlled borehole camera”, Ground Engineering, 3, 5, 20-21.

Borrelli, L., Greco, R., and Gullà, G., 2007, “Weathering grade of rock masses as a predisposing factor to slope instabilities: Reconnaissance and control procedures”, Geomorphology, 87, 158–175.

Clayton, C.R.I., Matthews, M.C. and Simons, N.E., 1982, “Site Investigation”, Second Edition, Department of Civil Engineering, University of Surrey, Halsted Press, p466.

Cleland, T.M., 1921, “A practical description of the Munsell colour system, with suggestions for its use”, Munsell Colour Company, Boston, USA.

Eggleton, R.A., Foudoulis, C., and Varkevisser, D., 1987, “Weathering of basalt: Changes in rock chemistry and mineralogy”, Clays and Clay Minerals, 35, 3, 161-169.

Eren, Y., 1993, “Eldes-Derbent-Tepekoy-Sogutozu (Konya) regions’ geolgy”, PhD Thesis, Selcuk University, Department of Geological Engineering, Konya, Turkey.

Geological Society of America, 1963, “Rock Colour Chart”, Geological Society of America, www.geosociety.org, Boulder, CO, USA.

Geological Society of London, 1977, “The description of rock masses for engineering purposes”, Engineering Group Working Party Report, Q. J. Eng. Geology, 10, 4, 355-388.

Gokay, M.K., 2003, “Effects of natural weathering of rock masses on their colour appearances”, Madencilik, Journal, Turkish Chambers of Mining Engineers, Mining Journal, (technical note), 42, 1, 35-42, Ankara, Turkey. (in Turkish).

Gokay, M.K. and Gundogdu, I.B., 2008, “Colour identification of some Turkish marbles”, Construction and Building Material, 22, 7, July 2008, 1342-1349.

Grossi, D., Del Lama, E.A., Garcia-Talegon, J., Inigo, A.C., Vicente-Tavera, S., 2015, “Evaluation of colourimetric changes in the Itequera granite of Ramos De Azevedo monument, Sao Paulo, Brazil”, International Journal of Conservation Science, 6, 3, 313-322, ISSN: 2067-533X

Heidari, M., Chastre, C., Torabi-Kaveh, M., Ludovico-Marques, M., Mohseni, H., 2017, “Application of fuzzy inference system for determining weathering degree of some monument stones in Iran”, Journal of Cultural Heritage, available online 25 January 2017.

Hunter, R.S., 1948, “Photoelectric colour-difference meter”, Proceedings of the Winter Meeting of the Optical Society of America, JOSA, 38, 7, 661.

Hunter, Labs., 1996, “Hunter Lab Colour Scale, Insight on Colour”, (August 1–15, 1996), Hunter Associates Laboratories, Reston, VA, USA.

Karpuz, C. and Pasamehmetoglu, A.G., 1997, “Field characterisation of weathered Ankara andesites”, Engineering Geology, 46, 1-17.

Munsell, A.H., 1905, “A Colour Notation”, G.H. Ellis Company, Boston,USA.

Patel, A.K. and Chatterjee, S., 2016, “Computer vision-based limestone rock-type classification using probabilistic neural network”, Geoscience Frontiers, 7, 1, Special Issue: Progress of Machine Learning in Geosciences, January 2016, 53-60.

Xlstat, 2017, “Data analysis and statistical solution for MS-Excel”, Addinsoft, Paris, France.

Vazquez, P., Carrizo, L., Thomachot-Schneider, C., Gibeaux, S., Alonso, F.J., 2016, “Influence of surface finish and composition on the deterioration of building stones exposed to acid atmospheres”, Construction and Building Materials, 106, 392–403.

Wikipedia, 2012, Wikipedia web-page, https://en.wikipedia.org/wiki/File: Triaxial_Ellipsoid.jpg

Yokoyama, T. and Nakashima, T.S., 2005, “Colour development of iron oxides during rhyolite weathering over 52,000 years”, Chemical Geology, 219, 309–320.