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Corrensite and chlorite-rich Chl-S mixed layers in sandstones from the ‘Macigno’ Formation (northwestern Tuscany, Italy)

Published online by Cambridge University Press:  09 July 2018

L. Leoni
Affiliation:
Dipartimento di Scienze della Terra, Università di Pisa, Via S. Maria 53, 56126 Pisa, Italy
M. Lezzerini
Affiliation:
Dipartimento di Scienze della Terra, Università di Pisa, Via S. Maria 53, 56126 Pisa, Italy
S. Battaglia*
Affiliation:
Institute of Geosciences and Earth Resources, National Research Council of Italy, Via G. Moruzzi 1, 56124 Pisa, Italy
F. Cavalcante
Affiliation:
Institute of Methodologies for Environmental Analysis, National Research Council of Italy, C.da S. Loja, 85050 Tito Scalo, Italy
*

Abstract

Corrensite and chlorite-rich chlorite-smectite (Chl-S) mixed-layers occurring in the Macigno Formation of northwestern Tuscany were investigated by XRPD/SEM techniques. The samples from the Macigno outcrops were affected by metamorphism corresponding to the high-diagenesis/low-anchizone transition boundary. The basal spacing of corrensite measured from 00l reflections on EG–Mg2+-saturated samples ranges from 30.97 to 31.18 Å with a coefficient of variation (CV) of 0.46–0.77%, consistent with the rational pattern of a 1:1 Chl-S periodic stacking sequence. X-ray patterns of heated K+-saturated specimens reveal the presence of two types of corrensite, probably with different interlayer charges on their respective smectite-like layers. The chlorite-rich Chl-S mixed layers coexisting with corrensite consist of R2 chlorite (0.70–0.75)/S and chlorite (0.90)/S with long-range ordering R ⩾ 1. SEM observations show that corrensite and chlorite-rich Chl-S mixed-layers are closely mixed on a sub-micron scale. Some grains of corrensite and chlorite-rich Chl-S mixed-layers include zones (2–10 μm) of chlorite composition, as shown by microprobe analyses.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2010

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References

Bailey, S.W. (1982) Nomenclature for regular interstratification. American Mineralogist, 67, 394398.Google Scholar
Bargossi, G.M., Di Battistini, G. & Zanollo, M. (1998) L'arenaria Macigno di Fivizzano (Massa Carrara). Eredita storico-culturale ed attuale georisorsa della Lunigiana. Mineralogica e Petrograflca Ada, 41, 267285.Google Scholar
Beaufort, D., Baronnet, A., Lanson, B. & Meunier, A. (1997) Corrensite: a single phase or mixed-layer phyllosilieate in the saponite-to-chlorite conversion series? A case study of Sancerre-Couy deep drill hole (France). American Mineralogist, 82, 109124.Google Scholar
Bonazzi, A., Salvioli Mariani, E. & Vernia, L. (1984) Diagenesi e metamorfismo dedotti dalla cristallinita dell'illite in formazioni sedimentarie affioranti tra Pontremoli e Salsomaggiore (Appennino Tosco—Emiliano). Mineralogica e Petrograflca Ada, 28, 123138.Google Scholar
Buatier, M., Fruh-Green, G.L. & Karpoff, A.M. (1996) Mechanism of Mg-phyllosilicates formation in a hydrothermal system at a sedimented ridge (Middle Valley, Juan de Fuca). Contributions to Mineralogy and Petrology, 122, 134151 Google Scholar
Cerrina, F.A., Plesi, G., Fanelli, G., Leoni, L. & Martinelli, P., (1983) Contribute alia conoscenza dei processi metamorfici (ancchimitamorfismo) a carico della Falda Toscana nell'area del ricoprimento apuano. Bollettino Società Geologica Italiana, 102, 269280.Google Scholar
Chang, H.K., MacKenzie, F.T. & Schoonmaker, J. (1986) Comparison between the diagenesis of dioetahedral and trioctahedral smectite, Brazilian offshore basins. Clays and Clay Minerals, 34, 407423.Google Scholar
Cipriani, C. (1958) Ricerche sui minerali costituenti le arenarie: I. Sulla eomposizione mineralogica della frazione argillosa di aleune arenarie macigno. Atti Societa Toscana Scienze Naturali, Memorie (Serie A), 65, 86107.Google Scholar
Cipriani, C. (1961) Ricerche sulle arenarie: III. La eomposizione mineralogica di aleune arenarie macigno. Periodico di Mineralogia, 30, 2359.Google Scholar
Cipriani, C. & Malesani, P. (1972) Composizione mineralogica delle formazioni pelitiche del Macigno e Marnoso Arenacea (Appennino settentrionale). Memorie Istituto Geologia Università Padova, 29, 124.Google Scholar
Cipriani, N., Malsani, P. & Vannucci, A. (1985) Distribuzione e rapporti dei sedimenti oligocenici e miocenici nell'Appennino settentrionale. Mineralogica e Petrograflca Ada, 24, 191210.Google Scholar
Di Battistini, G. & Rapetti, C. (2003) Pietra ornamentale e da costruzione nella Lunigiana. Arenaria. Silva Edotore, Parma, Italy. 269 pp.Google Scholar
Franzini, M., Leoni, L., Lezzerini, M. & Cardelli, R. (2007a) Relationships between mineralogical composition, water absorption and hydric dilatation in the ‘Macigno’ sandstones from Lunigiana (Massa, Tuscany). European Journal of Mineralogy, 19, 113123.CrossRefGoogle Scholar
Franzini, M., Leoni, L., Lezzerini, M., Gioncada, A. & Baglini, P. (2007b) Relazioni fra composizione mineralogica e proprietà fisiche nell'arenaria ‘Macigno’ del Monti d'Oltre Serchio (Toscana occidentale). Atti del IV congresso Nazionale di Archeometria, Pisa, Febbraio 2006. Patron Editore Bologna, Italy, 281295.Google Scholar
Krumm, S. (1996) WINFIT 1.2: version of November 1966 (The Erlangen geological and mineralogical software collection) of ‘WINFIT 1.0: a public domain program for interactive profile-analysis under WINDOWS’. XIII Conference on Clay Mineralogy and Petrology, Praha, 1994. Ada Universitatis Carolinae Geologica, 38, 253261.Google Scholar
Laird, J. (1988) Chlorite: metamorphic petrology. Pp. 405453 in: Hydrous Phyllosilicates (Bailey, S.W., editor). Reviews in Mineralogy, 19. Mineralogical Society of America.Google Scholar
Moore, D.M. & Reynolds, R.C. (1989) Identification of mixed-layered clay minerals. Pp. 241269 in: X-ray Diffraction and the Identification and Analysis of Clay Minerals (Moore, D.M. and Reynolds, R.C., editors), Oxford University Press, U.K. Google Scholar
Morandi, N. & Tateo, F. (1998) Significato della composizione mineralogica dei sedimenti pelitici nella sezione di Pignone (SP), Formazione del Macigno (Oligocene Superiore). Mineralogica e Petrografica Acta, 41, 193204.Google Scholar
Myklebust, R.L., Fiori, C.E. & Heinrich, K.F.S. (1978) FRAME C: a compact procedure for quantitative energy dispersive electron probe X-ray analysis. National Bureau Standard, Tech. Note no. 1106, US Dept. of Commerce, Washington, USA, 106 pp.Google Scholar
Reutter, K.J., Teichmüller, M., Teichmüller, R. & Zanzucchi, G. (1980) Le ricerche sulla carbonificazione dei fhistoli vegetali nelle rocce clastiche come contributo ai problemi di paleogeotermia e tettonica nelFAppennino settentrionale. Memorie Societa Geologica Italiana, 21, 111126.Google Scholar
Reynolds, R.C. (1980) Interstratified clay minerals. Pp. 249303 in: Crystal Structures of the Clay Minerals and their X-ray Identification (Brindley, G.W. & Brown, G., editors) Mineralogical Society Monograph 5, London, U.K. CrossRefGoogle Scholar
Reynolds, R.C. Jr. (1985) NEWMOD: a computer program for the calculation of the basal diffraction intensities of mixed-layered clay minerals. R.C. Reynolds, 8 Brook Rd., Hanover, New Hampshire, USA.Google Scholar
Shau, Y.H., Peacor, D.R. & Essene, J. (1990) Corrensite and mixed-layer chlorite/corrensite in metabasalt from northern Taiwan: TEM/AEM, EPMA, XRD and optical studies. Contributions to Mineralogy and Petrology, 105, 123142.CrossRefGoogle Scholar
Valloni, R. (1978) Provenienza e storia post-deposizionale del Macigno di Pontremoli (Massa). Bollettino Societa Geologica Italiana, 98, 317326.Google Scholar
Valloni, R., Lazzari, D. & Calzolari, M.A. (1991) Selective alteration of arkose framework in oligo-Miocene turbidites of the Northern Apennines foreland: impact on sedimentary provenance analysis. Pp. 125136 in: Developments in Sedimentary Provenance Studies (Morton, A.C., Todd, S.P. & P.Haughton, D.W., editors). Special Publications, 57, Geological Society, London,.Google Scholar
van de Kamp, P.C. & Leake, B.E. (1995) Petrology and geochemistry of siliciclastic rocks of mixed felds-pathic and ophiolitic provenance in the Northern Apennines, Italy. Chemical Geology, 122, 120.Google Scholar