Hostname: page-component-76fb5796d-45l2p Total loading time: 0 Render date: 2024-04-29T12:29:10.469Z Has data issue: false hasContentIssue false

Weathering of Iron-Bearing Minerals in Soils and Saprolite on the North Carolina Blue Ridge Front: I. Sand-Size Primary Minerals

Published online by Cambridge University Press:  02 April 2024

R. C. Graham*
Affiliation:
Department of Soil Science, North Carolina State University, Raleigh, North Carolina 27695
S. B. Weed
Affiliation:
Department of Soil Science, North Carolina State University, Raleigh, North Carolina 27695
L. H. Bowen
Affiliation:
Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695
S. W. Buol
Affiliation:
Department of Soil Science, North Carolina State University, Raleigh, North Carolina 27695
*
3Present address: Department of Soil and Environmental Sciences, University of California, Riverside, California 92521.

Abstract

The weathering products of primary biotite, chlorite, magnetite, and almandine in mica gneiss and schist in the North Carolina Blue Ridge Front were determined. Sand-size grains of biotite, the most abundant, readily weathered mineral in the parent rock, have altered to interstratified biotite/vermiculite, vermiculite, kaolinite, and gibbsite in the saprolite and soil. Fe2+-chlorite in the parent rock was relatively resistant to chemical weathering, which appears to be confined to the external surfaces of particles. Magnetite grains in the saprolite are essentially unaltered, but those in the soil contain abundant crystallographically controlled etch pits and are coated with oxidation crusts. Almandine altered to goethite, hematite, and gibbsite as the rock weathered to saprolite. Extensively weathered almandine grains were found to contain etch pits and what appeared to be oxide coatings. Apparently, a rapid release of Fe during weathering produced hematite, whereas slower release of Fe favored the formation of goethite.

Type
Research Article
Copyright
Copyright © 1989, The Clay Minerals Society

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Amarasiriwardena, D. D., DeGrave, E., Bowen, L. H. and Weed, S. B., 1986 Quantitative determination of aluminum-substituted goethite-hematite mixtures by Möss-bauer spectroscopy Clays & Clay Minerals 34 250256.CrossRefGoogle Scholar
Amthauer, G., Annersten, H. and Hafner, S. S., 1976 The Mössbauer spectrum of 57Fe in silicate garnets Z. Kristal-logr. 143 1455.CrossRefGoogle Scholar
Bain, D. C., 1977 The weathering of chloritic minerals in some Scottish soils J. Soil Sci. 28 144164.CrossRefGoogle Scholar
Barnhisel, R. I., Dixon, J. B. and Weed, S. B., 1977 Chlorites and hydroxy interlayered vermiculite and smectite Minerals in Soil Environments Wisconsin Soil Science Society of America, Madison 331356.Google Scholar
Blaauw, C., Stroink, G. and Leiper, W., 1980 Mössbauer analysis of talc and chlorite J. Phys. 41C1 411412.Google Scholar
Bowen, L. H., Weed, S. B. and Herber, R. H., 1984 Mössbauer spectroscopy of soils and sediments Chemical Mössbauer Spectroscopy New York Plenum 217242.CrossRefGoogle Scholar
Buoi, S. W. and Fadness, D. M., 1961 New method of impregnating fragile material for thin sectioning Soil Sci. Soc. Amer. Proc. 25 253.Google Scholar
Buoi, S. W., Hole, F. D. and McCracken, R. J., 1980 Soil Genesis and Classification Ames, Iowa Iowa State University Press.Google Scholar
Douglas, L. A., Dixon, J. B. and Weed, S. B., 1977 Vermiculites Minerals in Soil Environments Wisconsin Soil Science Society of America, Madison 259292.Google Scholar
Fanning, D. S., Keramidas, V. Z., Dixon, J. B. and Weed, S. B., 1977 Micas Minerals in Soil Environments Madison, Wisconsin Soil Science Society of America 195258.Google Scholar
Gilkes, R. J. and Suddhiprakarn, A., 1979 Magnetite alteration in deeply weathered adamellite J. Soil Sci. 30 357361.CrossRefGoogle Scholar
Golden, D. C., Bowen, L. H., Weed, S. B. and Bigham, J. M., 1979 Mössbauer studies of synthetic and soil-occurring aluminum substituted goethites Soil Sci. Soc. Amer. J. 43 802808.CrossRefGoogle Scholar
Graham, R.C., 1986 Geomorphology, mineral weathering, and pedology in an area of the Blue Ridge Front, North Carolina: Ph.D. dissertation North Carolina North Carolina State University, Raleigh.Google Scholar
Graham, R. C., Weed, S. B., Bowen, L. H., Amarasiriwardena, D. D. and Buoi, S. W., 1989 Weathering of iron-bearing minerals in soils and saprolite on the North Carolina Blue Ridge Front: II. Clay mineralogy Clays & Clay Minerals 37 2940.CrossRefGoogle Scholar
Greig, J. W., Posnjak, E., Merwin, H. E. and Sosman, R. B., 1935 Equilibrium relationships of Fe3O4, Fe2O3, and oxygen Amer. J. Sci. 230 239316.CrossRefGoogle Scholar
Grüner, J. W., 1926 Magnetite-martite-hematite Econ. Geol. 21 375393.CrossRefGoogle Scholar
Hargrove, R. S. and Kundig, W., 1970 Mössbauer measurements of magnetite below the Verwey Transition Solid State Comm. 8 303308.CrossRefGoogle Scholar
Harris, W. G., Zelazny, L. W. and Bloss, F.D., 1985 Biotite kaolinization in Virginia Piedmont soils: II. Zonation in single grains Soil Sci. Soc. Amer. J. 49 12971302.CrossRefGoogle Scholar
Losche, C. K., McCracken, R. J. and Davey, C. B., 1970 Soils of steeply sloping landscapes in the southern Appalachian Mountains Soil Sci. Soc. Amer. Proc. 34 473478.CrossRefGoogle Scholar
Murad, E. and Bowen, L. H., 1987 Magnetic ordering in Al-rich goethites: Influence of crystallinity A mer. Mineral. 72 194200.Google Scholar
Murad, E. and Schwertmann, U., 1986 Influence of Al substitution and crystal size on the room-temperature Mössbauer spectrum of hematite Clays & Clay Minerals 34 16.CrossRefGoogle Scholar
Murad, E. and Wagner, F. E., 1987 The Mössbauer spectrum of almandine Phys. Chem. Minerals 14 264269.CrossRefGoogle Scholar
Papamarinopoulos, S., Readman, P. W., Maniatis, Y. and Simopoulos, A., 1982 Magnetic characterization and Mössbauer spectroscopy of magnetic concentrates from Greek lake sediments Earth Planet. Sci. Letters 57 173181.CrossRefGoogle Scholar
Rebertus, R. A., Weed, S. B. and Buoi, S. W., 1986 Transformations of biotite to kaolinite during saprolite-soil weathering Soil Sci. Soc. Amer. J. 50 810819.CrossRefGoogle Scholar
Ross, G. J. and Kodama, H., 1974 Experimental transformation of a chlorite into a vermiculite Clays & Clay Minerals 22 205211.CrossRefGoogle Scholar
Sawhney, B. L., Dixon, J. B. and Weed, S. B., 1977 Interstratification in layer silicates Minerals in Soil Environments Wisconsin Soil Science Society of America, Madison 405434.Google Scholar
Schwertmann, U., 1985 The effect of pedogenic environments on iron oxide minerals Advances in Soil Science New York Springer-Verlag 170200.Google Scholar
Stuckey, J. L., 1965 North Carolina: Its Geology and Mineral Resources Raleigh, North Carolina North Carolina Dept. Conserv. Dev..Google Scholar
Velbel, M. A., 1984 Natural weathering mechanisms of almandine garnet Geology 12 631634.2.0.CO;2>CrossRefGoogle Scholar
Walker, A. L., 1983 The effects of magnetite on oxalate-and dithionite-extractable iron Soil Sci. Soc. Amer. J. 47 10221026.CrossRefGoogle Scholar