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Origin of clay minerals in the Bonarelli Horizon (Umbrian Apennines, central Italy)

Published online by Cambridge University Press:  09 July 2018

M. F. Brigatti  and
L. Poppi
M. F. Brigatti
Affiliation:
Istituto di Mineralogia e Petrografia, Università di Modena, Via S. Eufemia, 19-41100 Modena
L. Poppi
Affiliation:
Dipartimento di Scienze Mineralogiche, Università di Bologna-Piazza di Porta S. Donato, 1-40126 Bologna, Italy
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Abstract

Chemical, thermal, X-ray and statistical analyses were carried out on the clay fraction of the Bonarelli Horizon (Umbrian region, Central Italy) in order to investigate its origin. The vertical lithological sequence (organic carbon, siliceous and clay layers of varying colour and thickness) seems to change regularly, allowing the horizon to be subdivided into five sub-horizons (A to E). Sub-horizon B is clearly distinguishable from the others on the basis of the clay fractions. The presence of organic material and authigenic sulphates, constant chemical composition within a single sub-horizon, and regular repetition of the layers, show that the Bonarelli Horizon is the result of an alternation of anoxic events in a continental margin facies. A substantial contribution of volcanoclastic material is suggested for sub-horizon B.

Type
Research Article
Information
Clay Minerals , Volume 26 , Issue 1 , March 1991 , pp. 127 - 139
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1991

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References

Arthur, M.A. (1979) Sedimentology and geochemical studies of Cretaceous and Paleogene sedimentary rocks and some globalpaleoceanographic trends and events. Part 1. The Gubbio sequence. PhD dissertation, Princeton Univ., USA.Google Scholar
Bailey, S.W. (1980) Structure of layer silicates. Pp. 1-123 in: Crystal Structure of Clay Minerals and their X-ray Identification(Brindley, G.W. & Brown, G., editors). Mineralogical Society, London.Google Scholar
Bonarelli, G. (1891) II territorio di Gubbio. Notizie geologiche, Roma. Google Scholar
Brigatti, M.F. (1983) Relationships between composition and structure in Fe-rich smectites. Clay Miner. 18, 177–186.Google Scholar
Cooley, W.W. & Lohnes, P.R. (1971) Multivariate Data Analysis. J. Wiley & Sons, New York.Google Scholar
Curtis, C.D., IrelandB.J., Whiteman, J.A., Mulvaney, R. & Whittle, C.K. (1984) Authigenicchlorites: problems with chemical analysis and structural formula calculation. Clay Miner. 19, 471–481.Google Scholar
Humphreys, B., Smith, S.A. & Strong, G.E. (1989) Authigenic chlorites in late Triassic sandstones from the Central Graben, North sea. Clay Miner. 24, 427–444.Google Scholar
Jackson, M.L. (1979) Soil Chemical Analysis. Advanced Course. 2nd ed. Published by the author, Univ. Wisconsin, Madison, Wisconsin.Google Scholar
Jenkyns, H.C. (1980) Cretaceous anoxic events: from the continents to oceans. J. Geol. Soc. London, 137, 171–188.Google Scholar
Le Maitre, R.W. (1982) Numerical Petrology. Elsevier, New York.Google Scholar
Mackenzie, R.C. (1972) Differential Thermal Analysis. Academic Press, London.Google Scholar
Morrison, D.F. (1978) Multivariate Statistical Methods. McGraw-Hill, Auckland.Google Scholar
Nordsis, M.J. (1983) SPSSX Introductory Statistical Guide. McGraw-Hill, Auckland.Google Scholar
Ogniben, L., Parotto, M. & Praturlon, A. (1975) Structural model of Italy (maps and explanatory notes). Quad. Ricercha Scientifica 90, 502 Google Scholar
Shayan, A., Lancucki, C.J. & Way, S.J. (1987) Clay mineralogy of a watered granophyre from North Queensland, Australia. Proc. Int. Clay Conf., Denver 111–120.Google Scholar
Vannucci, S., Vannucci, R., Franchi, R. & Mazzucotelli, A. (1981) Presenza di livelli vulcanoclastici al tetto della Scaglia Bianca umbro-marchigiana. Rend. Soc. Ital. Miner. Petrol. 31t 105–131.Google Scholar