Hostname: page-component-cd9895bd7-jkksz Total loading time: 0 Render date: 2024-12-24T16:00:11.387Z Has data issue: false hasContentIssue false

The chemical composition of authigenic illite within two sandstone reservoirs as analysed by ATEM

Published online by Cambridge University Press:  09 July 2018

E. A. Warren
Affiliation:
Department of Geology, University of Sheffield, Mappin Street, Sheffield S3 7HF
C. D. Curtis
Affiliation:
Department of Geology, University of Sheffield, Mappin Street, Sheffield S3 7HF

Abstract

Analytical transmission electron microscopy (ATEM) was used to obtain chemical analyses of single illite crystals from Upper Carboniferous reservoir sandstones of the Bothamsall Oilfield, East Midlands, UK, and from Rotliegendes (Permian) sandstones of the North Sea. All samples were found to be highly aluminous, with only minor Mg and Fe, and to have near-ideal dioctahedral sheet totals. No significant variation in chemical composition of illite was found within the Bothamsall reservoir rocks, irrespective of paragenesis or stratigraphic horizon. Similar results were obtained from the Rotliegendes samples. Variation was found, however, between Bothamsall and Rotliegendes analyses populations. The Rotliegendes illites were distinctly more K-rich, which is the result of greater charge deficiency in the octahedral sheet. These results indicate that all the illite in both reservoirs precipitated in equilibrium with the reservoir pore-fluid. Furthermore, they imply that the physico-chemical composition of the pore-fluid did not evolve significantly between the different illite generations in the Bothamsall samples. These data, when compared with published analyses of authigenic illite, indicate that the compositional field for illite in sandstones is restricted in comparison with that of illite in mudrocks.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1989

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

Ahn, J.H. & Peacor, D.A. (1986) Transmission and analytical electron microscopy of the smectite-illite transition. Clays Clay Miner., 34, 165–169.Google Scholar
AIPEA (1986) Report of the AIPEA nomenclature committee: Illite. In: Association Internationale pour Vetnde des Argiles Newsletter, 22.Google Scholar
Bailey, S.W. (1980) Structures of the layer silicates. Pp. Crystal Strutures of Clay Minerals and their X-ray Identification(Brindley, G.W. and Brown, G., editors). Mineralogical Society, London, Monograph 5.Google Scholar
Deer, W.A., Howie, R.A. & Zussman J. (1962) Rock-Forming Minerals: 3. The Silicates. Longman, London.Google Scholar
Duplay, J. (1982) Analyses chimiques de populations de particules argileuses. Thése, Universite de Poitiers, 110 PP,Google Scholar
Duplay, J. (1984) Analyses chimiques ponctuelles de porticules d'rgiles. Relations entre variations de compositions dans une population de particules et temperature de formation. Sciences Geologique Bull. 37, 307–317.Google Scholar
Glennie, K. (1986) Early Permian-Rotliegend. Pp. 87109 in: Introduction to the Petroleum Geology of the North Sea (Glennie, K.W., editor). Blackwell, Oxford.Google Scholar
Hawkins, P.J. (1972) Carboniferous sandstone oil reservoirs, East Midlands, England.PhD thesis, University of London.Google Scholar
Hawkins, P.J. (1978) Relationship between diagenesis, porosity reduction and oil emplacement in late Carboniferous sandstone reservoirs, Bothamsall oilfield, E. Midlands. J. Geol. Soc. London 135, 7–24.Google Scholar
Huggett, J.M. (1982) The growth and origin of authigenic clay minerals in sandstones. PhD Thesis, University of London.Google Scholar
Huggett, J.M. (1984) Controls on mineral authigenesis in Coal Measures sandstones of the East Midlands, U.K. Clay Miner. 19, 343–357.Google Scholar
Huggett, J.M. (1986) An SEM study of phyllosilicate diagenesis in sandstones and mudstones in the Westphalian Coal Measures using back-scattered electron microscopy. Clay Miner. 21, 603–616.CrossRefGoogle Scholar
Hughes, C.R. (1987) The composition and origin of layer silicates in iron-formations and ironstones: a preliminary analytical transmission electron microscopical study. PhD thesis, University of Sheffield.Google Scholar
Hughes, C.R., Curtis, C.D., Whiteman, J.A., Sun, Heping, Whittle, C.K. & Ireland, B.J. (1989) Applications of analytical electron microscopy in clay mineralogy. In: Microscopical Methods of Analysis of Clay Minerals (Mackinnon, I.D.R., editor). Clay Minerals Society, USA.Google Scholar
Ireland, B.J. (1982) Transmission electron microscopy of authigenic clay minerals. PhD thesis, University of SheffieldGoogle Scholar
Ireland, B.J., Curtis, C.D. & Whiteman, J.A. (1983) Compositional variation within some glauconites and illites and implications for their stability and origins. Sedimentology 30, 769–786.CrossRefGoogle Scholar
Kent, P.E. (1980) Subsidence and uplift in East Yorkshire and Lincolnshire: a double inversion. Proc. York. Geol. Soc. 42, 505–524.Google Scholar
Merino, E. & Ransom, B. (1982) Free energies of formation of illite solid solutions and their compositional dependence. Geochim. Cosmochim. Acta 30, 29–39.Google Scholar
Nadeau, P.H., Tait, J.M., McHardy, W.J. & Wilson, M.J. (1984) Interstratified XRD characteristics of physical mixtures of elementary clay particles. Clay Miner. 19, 67–76.Google Scholar
Newman, A.C.D. (editor) (1987) Chemistry of Clays and Clay Minerals. Mineralogical Society, London, Monograph 6.Google Scholar
Phakey, P.P., Curtis, C.D. & Oertel, G. (1972) Transmission electron microscopy of fine-grained phyllosilicates in ultra-thin rock sections. Clays Clay Miner. 20, 193–197.CrossRefGoogle Scholar
Pye, K. & Krinsley, D.H. (1986) Diagenetic carbonate and evaporite in Rotliegend aeolian sandstones of the Southern North Sea: their nature and relationship to secondary porosity development. Clay Miner. 21, 443458.Google Scholar
Reynolds, R.C. (1980) Interstratified clay minerals. Pp. 249303 in: Crystal Structures of Clay Minerals and their X-ray Identification (Brindley, G.W. and Brown, G., editors). Mineralogical Society, London, Monograph 5.CrossRefGoogle Scholar
Smith, E.G., Rhys, G.H. & Goosens, R.F. (1973) Geology of the Country around East Retford, Worksop and Gainsborough. HMSO, London.Google Scholar
Srodon, J. & Eberl, D.D. (1984) Illite. Pp. 495544 in: Micas. Reviews in Mineralogy 13 (Bailey, S.W., editor). Mineralogical Society of America.Google Scholar
Velde, B. (1977) A proposed phase diagram for illite, expanding chlorite, corrensite and illite-montmorillonite mixed layered minerals. Clays Clay Miner. 25, 264–270.CrossRefGoogle Scholar
Velde, B. (1984) Clay Minerals: A Physico-Chemical Explanation of their Occurrence(Developments in Sedimentology, 40), Elsevier, Amsterdam & New York, 427 pp.Google Scholar
Warren, E.A. (1987a) Geochemistry of authigenic mineral sequences in sandstones. PhD thesis. University of Sheffield.Google Scholar
Warren, E.A. (1987b) The application of a solution-mineral equilibrium model to the diagenesis of Carboniferous sandstones, Bothamsall oilfield, East Midlands, England. Pp. 5369 in: Diagenesis of Sedimentary Sequences (Marshall, J.D., editor). Geological Society, London, Special Publication 36.Google Scholar
Weaver, C.E. & Pollard, L.D. (1973) The Chemistry of Clay Minerals(Developments in Sedimentology, 15). Elsevier, Amsterdam & New York, 272 pp.Google Scholar
Wilson, M.J. (editor) (1987) A Handbook of Determinative Methods in Clay Mineralogy. Blackie, Glasgow, 308 PP.Google Scholar