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Geology and Characterization of Two Hydrothermal Nontronites from Weathered Metamorphic Rocks at the Uley Graphite Mine, South Australia

Published online by Cambridge University Press:  28 February 2024

John L. Keeling ,
Mark D. Raven  and
Will P. Gates
John L. Keeling*
Affiliation:
Primary Industries and Resources, South Australia, GPO Box 1617, Adelaide, SA 5001 Australia
Mark D. Raven
Affiliation:
CSIRO Land and Water, PMB No. 2, Glen Osmond, SA 5064 Australia
Will P. Gates
Affiliation:
CSIRO Land and Water, PMB No. 2, Glen Osmond, SA 5064 Australia
*
E-mail of corresponding author: keeling.john@saugov.sa.gov.au
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Abstract

Mining operations during the early 1990s at Uley Graphite Mine near Port Lincoln on southern Eyre Peninsula, South Australia, uncovered abundant nontronite veins in deeply weathered granulite facies schist, gneiss, and amphibolite of Palaeoproterozoic age. Two types of nontronite are present: a bright yellowish-green clay (NAu-1) distributed as veinlets and diffuse alteration zones within kaolinized schist and gneiss, and a massive to earthy, dark-brown clay (NAu-2) infilling fracture networks mainly in amphibolite or basic granulite. The nontronites are the product of low-temperature hydrothermal alteration of primary minerals, biotite, and amphibole. The principal chemical difference between NAu-1 and NAu-2 is a higher alumina content in NAu-1, which was either inherited during hydrothermal alteration of biotite in the host rock or acquired through recrystallization of nontronite during subsequent weathering and associated kaolinization. Sufficient bulk samples of both NAu-1 and NAu-2 were collected to supplement reference nontronite of the Source Clay Repository of The Clay Minerals Society. The clay fraction of the bulk samples is typically >85%. NAu-1 contains minor kaolin and quartz which are easily removed to give a high purity nontronite of composition M+1.05[Si6.98Al1.02][Al0.29Fe3.68Mg0.04]O20(OH)4, similar to that of nontronite from Garfield, Washington. NAu-2 contains fewer total impurities but the presence of trace amounts of submicron carbonate and iron oxyhydroxide requires additional chemical treatment to produce a nontronite of purity comparable to NAu-1. Composition of NAu-2 was calculated as M+0.72[Si7.55Al0.45][Fe3.83Mg0.05]O20(OH)4, although infrared data indicate that at least some Fe is in tetrahedral coordination.

Keywords

Amphibole AlterationBiotite AlterationHydrothermal AlterationInfrared SpectroscopyNAu-1NAu-2NontroniteWeatheringX-ray Diffraction
Type
Research Article
Information
Clays and Clay Minerals , Volume 48 , Issue 5 , October 2000 , pp. 537 - 548
Copyright
Copyright © 2000, The Clay Minerals Society

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References

Anand, R.R. and Gilkes, R.J., (1984) Weathering of hornblende, plagioclase and chlorite in meta-dolerite, Australia Geoderma 34 261–280 10.1016/0016-7061(84)90043-0.CrossRefGoogle Scholar
Banfield, J.F. and Barker, W.W., (1993) Direct observation of reactant-product interfaces in natural weathering of exsolved, defective amphibole to smectite: Evidence for episodic, isovolumetric reactions involving structural inheritance Geochimica et Cosmochimica Acta 58 1419–1429 10.1016/0016-7037(94)90546-0.CrossRefGoogle Scholar
Benbow, M.C., (1992) A review of past climate with emphasis on the recent past—a framework for the future Mines and Energy Review, South Australia 158 5–20.Google Scholar
Benbow, M.C. Callen, R.A. Bourman, R.P. Alley, N.E., Drexel, J.F. and Preiss, W.V., (1995) Deep weathering, ferricrete and silcrete The Geology of South Australia. Volume 2, The Phanerozoic Adelaide South Australia Geological Survey Bulletin 54 201–207.Google Scholar
Bender Koch, C. Morup, S. Madsen, M.B. and Vistisen, L., (1995) Iron-containing weathering products of basalt in a cold, dry climate Chemical Geology 122 109–119 10.1016/0009-2541(95)00002-4.CrossRefGoogle Scholar
Berner, R.A. and Schott, J., (1982) Mechanism of pyroxene and amphibole weathering II. Observation of soil grains American Journal of Science 282 1214–1231 10.2475/ajs.282.8.1214.CrossRefGoogle Scholar
Besson, G. Bookin, A.S. Dainak, L.G. Rautereau, M. Tsi-pursky, SI Tchoubar C and Drits, V.A., (1983) Use of diffraction and Mössbauer methods for the structural and crystallochemical characterization of nontronites Journal of Applied Crystallography 16 374–383 10.1107/S0021889883010651.CrossRefGoogle Scholar
Bischoff, J.L., (1972) A ferroan nontronite from the Red Sea geothermal system Clays and Clay Minerals 20 217–223 10.1346/CCMN.1972.0200406.CrossRefGoogle Scholar
Bodine, M.W. Jr, (1987) CLAYFORM: A Fortran 77 computer program apportioning the constituents in the chemical analysis of a clay or other silicate mineral into a structural formula Computers and Geosciences 13 77–88 10.1016/0098-3004(87)90025-2.CrossRefGoogle Scholar
Bonnin, D. Calas, G. Suquet, H. and Pezerat, H., (1985) Sites occupancy of Fe3+ in Garfield nontronite. A spectroscopic study Physics and Chemistry of Minerals 12 55–64.CrossRefGoogle Scholar
Bradley, G.M., (1980) Metamorphism of the Archaean and Proterozoic basement at southern Eyre Peninsula Journal of the Geological Society of Australia 25 199–218.Google Scholar
Cardile, C.M. and Johnston, J.H., (1985) Structural studies of nontronites with different iron contents by 57Fe Mössbauer spectroscopy Clays and Clay Minerals 33 295–300 10.1346/CCMN.1985.0330404.CrossRefGoogle Scholar
Drexel, J.E. Priess, W.V. and Parker, A.J., (1993) The Geology of South Australia. Volume 1, The Precambrian Adelaide Geological Survey of South Australia Bulletin 54.Google Scholar
Eggleton, R.A., (1975) Nontronite topotaxial after hedenber-gite American Mineralogist 60 1063–1068.Google Scholar
Eggleton, R.A., (1977) Nontronite: Chemistry and X-ray diffraction Clay Minerals 12 181–194 10.1180/claymin.1977.012.3.01.CrossRefGoogle Scholar
Goodman, B.A. Russell, J.D. Fraser, A.R. and Woodhams, F.W.D., (1976) A Mossbauer and I.R. spectroscopic study of the structure of nontronite Clays and Clay Minerals 24 53–59 10.1346/CCMN.1976.0240201.CrossRefGoogle Scholar
Köhler, B. Singer, A. and Stoffers, P., (1994) Biogenic nontronites from marine white smoker chimneys Clays and Clay Minerals 42 689–701 10.1346/CCMN.1994.0420605.CrossRefGoogle Scholar
Manceau, A. Chateigner, D. and Gates, W.P., (1998) Polarized EXAFS, distance-valance least-squares modelling (DLVS), and quantitative texture analysis approaches to the structural refinement of Garfield nontronite Physics and Chemistry of Minerals 25 347–365 10.1007/s002690050125.CrossRefGoogle Scholar
McNally, T.C., (1997) Uley graphite deposit MESA Journal 5 16–18.Google Scholar
Murad, E. Cashion, J.D. and Brown, L.J., (1990) Magnetic ordering in Garfield nontronite under applied magnetic fields Clay Minerals 25 261–269 10.1180/claymin.1990.025.3.02.CrossRefGoogle Scholar
Murnane, R. and Clauge, D.A., (1983) Nontronite from a low-temperature hydrothermal system on the Juan de Fuca Ridge Earth and Planetary Science Letters 65 343–352 10.1016/0012-821X(83)90172-3.CrossRefGoogle Scholar
Norrish, K. and Hutton, J.T., (1969) An accurate X-ray spec-trographic method for the analysis of a wide range of geologic samples Geochimica et Cosmochimica Acta 33 431–451 10.1016/0016-7037(69)90126-4.CrossRefGoogle Scholar
Parker, A.J., Drexel, J.F. Preiss, W.V. and Parker, A.J., (1993) Palaeoproterozoic The Geology of South Australia. Volume. 1, The Precambrian Adelaide Geological Survey of South Australia Bulletin 54 51–105.Google Scholar
Ross, C.S. and Hendricks, S.B., (1945) Minerals of the Mont-morillonite Group Washington D.C. U.S. Geological Survey Professional Paper 205-B 23–79.Google Scholar
Taylor, J.C., (1991) Computer programs for standardless quantitative analysis of minerals using the full powder diffraction profile Powder Diffraction 6 2–9 10.1017/S0885715600016778.CrossRefGoogle Scholar
Taylor, J.C. and Matulis, C.E., (1994) A new method for Rietveld clay analysis. Part I. Use of a universal measured standard profile for Rietveld quantification of montmorillonites Powder Diffraction 9 119–123 10.1017/S0885715600014093.CrossRefGoogle Scholar
Taylor, W.R. and Berry, R.E., (1990) Origin of the Proterozoic graphite deposits of the southern Eyre Peninsula, South Australia—constraints from stable isotope geochemistry Geological Society of Australia, 10th Australian Geological Convention, Hobart 1990, Abstracts 25 230–231.Google Scholar
Velbel, M.A., (1989) Weathering of hornblende to ferruginous products by a dissolution-reprecipitation mechanism: Petrography and stoichiometry Clays and Clay Minerals 37 515–524 10.1346/CCMN.1989.0370603.CrossRefGoogle Scholar
Yeomans, J.C. and Bremer, J.M., (1991) Carbon and nitrogen analysis of soils by automated combustion techniques Communications in Soil Science and Plant Analysis 22 843–850 10.1080/00103629109368458.CrossRefGoogle Scholar