Hostname: page-component-78c5997874-j824f Total loading time: 0 Render date: 2024-11-10T06:28:30.290Z Has data issue: false hasContentIssue false
  • English
  • Français

Submicroscopic Structure of Fe-Coatings on Quartz Grains in Tropical Environments

Published online by Cambridge University Press:  28 February 2024

E. Padmanabhan  and
A. R. Mermut
E. Padmanabhan
Affiliation:
Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5A8, Canada
A. R. Mermut
Affiliation:
Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, S7N 5A8, Canada
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Formation of Fe-coatings or segregation at the expense of quartz grains is a common process in the tropical environment. Limited information is available about their internal structure at the submicroscopic level. The transmission electron microscope (TEM) and energy dispersive X-ray microprobe analyses (EDXRMA) techniques were used to identify the nature and arrangement of fundamental mineral particles within the Fe-coatings. Chemical and mineralogical studies showed that the coatings were composed of well-crystallized Fe-oxides, quartz and kaolinite. The EDXRMA analyses revealed the presence of linear concentrations (laminae) of nearly pure Fe oxide along the edges and the contact zone with quartz and within the coatings. Similar atomic proportions of Al and Si in several areas within the interior regions of coatings and the XRD pattern of the crushed coatings are supportive evidence for the presence of kaolinite. Under the TEM, the dense laminae (< 10 μm thick) consisted of elongated Fe-oxide particles (< 1.5 μm long and 0.2 μm thick) accommodated in subparallel arrangement. The interior areas had very high porosity and, in addition to Fe-oxides, contained other minerals: mainly kaolinite, quartz and isolated areas of Al-oxides. High amounts of ultramicroscopic pores (<0.5 μm) in the interior region suggested that dissolution of Fe-oxides occurred under reduced conditions, with subsequent reprecipitation of pure Fe-oxides in the laminae. Very low porosity and parallel arrangement of Fe-oxide particles (laminae) provided new surfaces (barrier) for Fe-accumulation when soil solutions provided new influxes of iron, thereby creating a thicker Fe-coating. The size and geometry of the ultramicroporosity were shown to play a significant role in the dissolution and precipitation of soil minerals, especially those involved in redox reactions.

Keywords

Electron MicroscopyFe-coatingFe-nodulesFe-oxide FormsSubmicroscopic StructureUltrathin SectionsX-ray Microprobe Analysis
Type
Research Article
Information
Clays and Clay Minerals , Volume 44 , Issue 6 , December 1996 , pp. 801 - 810
Copyright
Copyright © 1996, The Clay Minerals Society

References

Amouric, M., Baronnet, A., Nahon, D. and Didier, P.. 1986. Electron microscopic investigations of iron oxyhydroxides and accompanying phases in lateritic iron-crust pisolites. Clays Clay Miner 34: 45–52.CrossRefGoogle Scholar
Arshad, M.A. and St. Arnaud, R.J.. 1980. Occurrence and characteristics of ferromanganiferous concretions in some Saskatchewan soils. Can J Soil Sci 60: 685–695.CrossRefGoogle Scholar
Bascomb, C.L.. 1968. Distribution of pyrophosphate-extractable iron and organic carbon in soils of various groups. J Soil Sci 19: 251–268.CrossRefGoogle Scholar
Brewer, R.. 1976. Fabric and mineral analysis of soils. Melbourne, FL: Robert E. Kriger. 482 p.Google Scholar
Bruemmer, G.W., Gerth, J. and Tiller, K.G.. 1988. Reaction kinetics of the adsorption and desorption of nickel, zinc and cadmium by goethite: I. Adsorption and diffusion of metals. Soil Sci 39: 37–52.CrossRefGoogle Scholar
Bui, E.N., Mermut, A.R. and Santos, M.C.D.. 1989. Microscopic and ultramicroscopic porosity of an Oxisol as determined by image analyses and water retention. Soil Sci Soc Am J 53: 661–665.CrossRefGoogle Scholar
Bullock, P., Fedoroff, N., Jongerius, A., Stoops, G., Tursina, T. and Babel, U.. 1985. Handbook for soil thin section description. Wolverhampton, UK: Waine Research. 152 p.Google Scholar
Cescas, M.P., Tyner, E.H. and Harmer, R.S.. 1970. Ferro-manganiferous soil concretions: a scanning electron microscopic study of their micropore structure. Soil Sci Soc Am Proc 34: 641–644.CrossRefGoogle Scholar
Cho, H.D. and Mermut, A.R.. 1992. Evidence for halloysite formation from the weathering of ferruginous chlorite. Clays Clay Miner 40: 608–619.Google Scholar
Eswaran, H., Lim, C.H., Sooryanarayana, V. and Daud, Nordin. 1978. Scanning electron microscopy of secondary minerals in Fe-Mn glaebules. In: Delgado, M., editor. Soil micromorphology. Proceedings of the 5th international working meeting on soil micromorphology; Grenada, Spain. Grenada: Departmento de Edafologia, Univ de Granada. p 589–609.Google Scholar
Eswaran, H. and Stoops, G.. 1979. Surface textures of quartz in tropical soils. Soil Sci Soc Am J 43: 420–424.CrossRefGoogle Scholar
Eswaran, H., Sys, C. and Sousa, E.C.. 1975. Plasma infusion—a pedological process of significance in the humid tropics. Anales de Edafologia y Agrobiologia 34: 665–673.Google Scholar
Gallaher, R.N., Perkins, H.F. and Radcliffe, D.. 1973. Soil concretions: I. X-ray spectrograph and electron microprobe analysis. Soil Sci Soc Am Proc 37: 465–469.CrossRefGoogle Scholar
Gallaher, R.N., Perkins, H.F., Tan, K.H. and Radcliffe, D.. 1973. Soil concretions: II. Mineralogical analysis. Soil Sci Soc Am Proc 37: 469–472.CrossRefGoogle Scholar
Ghabru, S.K., St. Arnaud, R.J. and Mermut, A.R.. 1987. Liquid magnetic separation of iron-bearing minerals from sand fractions of soils. Can J Soil Sci 67: 561–569.CrossRefGoogle Scholar
Herbillon, A.J. and Tran, V.A.J.. 1969. Heterogeneity in silicon-iron mixed hydroxides. J Soil Sci 20: 223–235.CrossRefGoogle Scholar
Jackson, M.L.. 1973. Soil chemical analysis—advanced course. 2nd ed, 8th printing. Madison, WI: ML Jackson, Univ of Wisconsin. 895 p.Google Scholar
Jones, R.C. and Uehara, G.. 1973. Amorphous coatings on mineral surfaces. Soil Sci Soc Am Proc 37: 792–798.CrossRefGoogle Scholar
Krauskopf, K.B.. 1967. Introduction to geochemistry. New York: McGraw-Hill. 721 pGoogle Scholar
Lewis, D.G. and Schwertmann, U.. 1979. The influence of aluminium on the formation of iron oxides: IV. The influence of (Al), (OH) and temperature. Clays Clay Miner 27: 195–200.CrossRefGoogle Scholar
McKeague, J.A. and Day, J.H.. 1966. Dithionite- and oxalate-extractable Fe and Al as aids in differentiating various classes of soils. Can J Soil Sci 46: 13–22.CrossRefGoogle Scholar
Mehra, O.P. and Jackson, M.L.. 1960. Iron oxides removal from soils and clays by a dithionite-citrate system buffered with sodium bicarbonate. Clays Clay Miner 7: 317–327.CrossRefGoogle Scholar
Milnes, A.R. and Fitzpatrick, R.W.. 1989. Titanium and zirconium minerals. In: Dixon, J.B., Weed, S.B., editors. Minerals in soil environments. 2nd ed. Madison, WI: Soil Science Society of America. p 1132–1205.Google Scholar
Mohr, E.C.J., van Baren, F.A. and van Schuylenbourgh, J.. 1972. Tropical soils: a comprehensive study of their genesis. The Netherlands: Geuze Dordrecht. 481 p.Google Scholar
Nahon, D.B.. 1991. Self-organization in chemical lateritic weathering. Geoderma 51: 5–13.CrossRefGoogle Scholar
Padmanabhan, E. and Mermut, A.R.. 1995. The problem in expressing the specific surface areas of clay fractions. Clays Clay Miner 43: 237–245.CrossRefGoogle Scholar
Pawluk, S. and Dumanski, J.. 1973. Ferruginous concretions in a poorly drained soil of Alberta. Soil Sci Soc Am Proc 37: 124–127.CrossRefGoogle Scholar
Plançon, A., Giese, R.F. and Snyder, R.. 1988. The Hinckley Index for kaolinites. Clay Miner 23: 249–260.CrossRefGoogle Scholar
Santos, M.C.D., Mermut, A.R. and Ribeiro, M.R.. 1989. Submicroscopy of clay microaggregates in an Oxisol from Pernambuco, Brazil. Soil Sci Soc Am J 53: 1895–1901.CrossRefGoogle Scholar
Schwertmann, U.. 1985. Occurrence and formation of iron oxides in various pedoenvironments. In: Stucki, J.W., Goodman, B.A., Schwertmann, U., editors. Iron in soils and clay minerals. NATO ASI Series C: Mathematical and Physical Sciences, vol 217. Boston: D. Reidel. p 267–308.Google Scholar
Schwertmann, U., Fitzpatrick, R.W. and Le Roux, J.. 1977. Al-substitution and differential disorder in soil hematites. Clays Clay Miner 25: 373–374.CrossRefGoogle Scholar
Schwertmann, U., Fitzpatrick, R.W., Taylor, R.M. and Lewis, D.G.. 1979. The influence of aluminium on iron oxides: Part II. Preparation and properties of Al-substituted hematites. Clays Clay Miner 27: 105–112.CrossRefGoogle Scholar
Schwertmann, U. and Taylor, R.M.. 1989. Iron oxides. In: Dixon, J.B., Weed, S.B., editors. Minerals in soil environments. 2nd ed. Madison, WI: Soil Science Society of America. p 379–438.Google Scholar
Shadfan, H., Dixon, J.B. and Calhoun, F.G.. 1985. Iron oxide properties versus strength of ferruginous crust and iron-glaebules in soils. Soil Sci 140: 317–325.CrossRefGoogle Scholar
Sherman, G.D. and Kanehiro, Y.. 1954. Origin and development of ferruginous concretions in Hawaiian Latosols. Soil Sci 77: 1–8.CrossRefGoogle Scholar
Smart, P. and Tovey, K.. 1982. Electron microscopy of soils and sediments: techniques. Oxford: Clarendon Pr. 264 p.CrossRefGoogle Scholar
Sposito, G. and Reginato, R.J., editors. 1992. Opportunities in basic soil science research. Madison, WI: Soil Science Society of America. 109 p.CrossRefGoogle Scholar
Spurr, A.R.. 1969. A low-viscosity epoxy embedding medium for electron microscopy. J Ultrastruct Res 26: 31–43.CrossRefGoogle ScholarPubMed
Tardy, Y. and Nahon, D.. 1985. Geochemistry of laterites, stability of Al-goethite, Al-hematite, and Fe3+-kaolinite in bauxites and ferricretes: an approach to the mechanism of concretion formation. Am J Sci 285: 865–903.CrossRefGoogle Scholar
Taylor, R.M. and Schwertmann, U.. 1974. The association of phosphorous with iron in ferruginous soil concretions. Aust J Soil Res 12: 133–145.CrossRefGoogle Scholar
Tiessen, H., Frossard, E., Mermut, A.R. and Nyamekye, A.L.. 1991. Phosphorous sorption and properties of ferruginous nodules from semiarid soils from Ghana and Brazil. Geoderma 48: 373–389.CrossRefGoogle Scholar
Trolard, F. and Tardy, Y.. 1989. A model of Fe3+-kaolinite, Al3+-goethite, Al3+-hematite equilibria in laterites. Clay Miner 24: 1–21.CrossRefGoogle Scholar
Vempati, R.K., Loeppert, R.H. and Sittertz-Bhatkar, H.. 1990. Infrared vibration of hematite formed from aqueous and dry thermal incubation of Si-containing ferrihydrite. Clays Clay Miner 38: 294–298.CrossRefGoogle Scholar