Hostname: page-component-848d4c4894-r5zm4 Total loading time: 0 Render date: 2024-06-26T22:47:37.903Z Has data issue: false hasContentIssue false

Evolution of Illite/Smectite from Early Diagenesis Through Incipient Metamorphism in Sediments of the Basque-Cantabrian Basin

Published online by Cambridge University Press:  28 February 2024

F. Nieto
Affiliation:
Departamento Mineralogia y Petrologia and I.A.C.T. Universidad de Granada-C.S.I.C. 18002 Granada, Spain
M. Ortega-Huertas
Affiliation:
Departamento Mineralogia y Petrologia and I.A.C.T. Universidad de Granada-C.S.I.C. 18002 Granada, Spain
D. R. Peacor
Affiliation:
Department of Geological Sciences. The University of Michigan, Ann Arbor, Michigan 48109, USA
J. Arostegui
Affiliation:
Departamento Mineralogia y Petrologia. Universidad del Pais Vasco. Lejona, Bilbao, Spain

Abstract

Prograde evolution of illite/smectite occurring in an unusually-thick (8000 m) sequence of Mesozoic-Cenozoic sediments in the Basque-Cantabrian Basin, Spain, has been studied using XRD and TEM/AEM. The sediments, which are only slightly tilted, cover the range from smectite to illite, and the most deeply buried ones are unique in that they span the range from diagenesis through low-grade metamorphism (anchizone), with no apparent overprinting due to tectonic deformation.

Pelites are absent from the shallow section, but smectite occurs in marls as high-charge, K-dominant and low-charge, K-poor anastomosing arrays of layers. At intermediate depths, authigenic clay is identified largely as R1 I/S, coexisting with packets of R≫3 I/S (nearly pure illite), where illite-like and smectitelike layers can be identified by contrast in TEM images, which is consistent with XRD data. The authigenic clay of the deepest samples consists of illite with no or almost no expandable layers, which occurred as packets with layers largely subparallel to bedding, K-deficient composition in comparison with muscovite, 1Md-like SAED patterns, and 100 Å mean packet thickness. There is no evidence of deformation stress-induced, non-bedding-parallel clays in the deepest samples. Detrital micas with either a phengiterich or a phengite-poor composition range dominate the phyllosilicate fraction of all the samples. Detrital micas show no changes over the diagenesis/metamorphism range and appear to have behaved as if isolated from authigenic clays.

Authigenic clays occur as bedding-subparallel packets that evolved during passive burial metamorphism through dissolution/crystallization of less-evolved clays. Where illite-like and smectite-like layers can be identified, TEM images imply a discontinuous series in which packets of R1 I/S (50% I) transform to packets of nearly-pure illite, that is, an Ostwald-step-rule-like sequence. Such immature illite remains unmodified with further burial, and is apparently the potential predecessor of stress-induced, highly-evolved mica of higher-grade, tectonically-deformed pelites.

Type
Research Article
Copyright
Copyright © 1996, 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

Ahn, J.H. and Peacor, D.R.. 1986. Transmission electron microscope data for rectorite: Implications for the origin and structure of “fundamental particles”. Clays & Clay Miner 34: 180186.Google Scholar
Amiot, M., Floquet, M., Mathey, B., Pascal, A. and Salomon, J.. 1982. Evolution de la marge cantabrique et son arrière-pays iberique au Crétacé. Cuad Geol Ibérica 8: 3763.Google Scholar
Aróstegui, J., Zuluaga, M.C., Velasco, F., Ortega Huertas, M. and Nieto, F.. 1991. Diagenesis of the Central Basque-Cantabrian basin (Iberian Peninsula) based on illite-smectite distribution. Clay Miner 26: 535548.CrossRefGoogle Scholar
Aróstegui, J., Nieto, F., Ortega Huertas, M., Velasco, F. and Zuluaga, M.C.. 1993. Mineralogía de arcillas y grado de diagénesis del Cretácico Inferior, en el flanco sur del anticlinorio de Bilbao. Est Geol 49: 277286.CrossRefGoogle Scholar
Baxter, S.M. and Peacor, D.R.. 1991. TEM observations of polytypism in illite. Clays & Clay Miner 39: 540550.CrossRefGoogle Scholar
Bell, T.E.. 1986. Microestructure in mixed-layer illite/smectite and its relationship to the reaction of smectite to illite. Clays & Clay Miner 34: 146154.CrossRefGoogle Scholar
Boles, J.R. and Franks, S.G.. 1979. Clay diagenesis in Wilcox sandstones of Southwest Texas: implications of smectite diagenesis on sandstone cementation. J Sediment Petrol 49: 5570.Google Scholar
Buatier, M.D., Peacor, D.R. and O'Neil, J.R.. 1992. Smectite-illite transition in Barbados accretionary wedge sediments: TEM and AEM evidence for a dissolution/crystallization origin at low temperature. Clays & Clay Miner 40: 6580.CrossRefGoogle Scholar
Cathelineau, M. and Nieva, D.. 1985. A chlorite solid solution geo-thermometer. The Los Azufres (Mexico) geothermal system. Contrib Mineral Petrol 91: 235244.CrossRefGoogle Scholar
Chamley, H.. 1989. Clay Sedimentology. Berlin: Springer. 620 p.CrossRefGoogle Scholar
Champness, P.E., Cliff, G. and Lorimer, G.W.. 1981. Quantitative analytical electron microscopy. Bull Mineral 104: 236240.Google Scholar
Cliff, G. and Lorimer, G.W.. 1975. The quantitative analysis of thin specimens. J Microsc 103: 203207.CrossRefGoogle Scholar
Crowley, S.F.. 1991. Diagenetic modification of detrital muscovite: An example from the Great Limestone Ciclotem (Carboniferous) of Co. Durham, UK. Clay Miner 26: 91103.CrossRefGoogle Scholar
Deregnaucourt, D. and Boillot, G.. 1982. Structure géologique du golfe de Gascogne. Bull du BRGM 2: 149178.Google Scholar
Dickens, G.. 1994. Personal communication. Department of Geological Sciences, The University of Michigan, 1006 CC. Little Building, Ann Arbor, MI 48109–1063.Google Scholar
Dong, H.. 1994. Personal communication. Department of Geological Sciences, The University of Michigan, 1006 CC. Little Building, Ann Arbor, MI 48109–1063.Google Scholar
Eberl, D.D.. 1993. Three zones for illite formation during burial diagenesis and metamorphism. Clays & Clay Miner 41: 2637.CrossRefGoogle Scholar
Foscolos, A.E., Powell, T.G. and Gunther, P.R.. 1976. The use of clay minerals and inorganic and organic geochemical indicator for evaluating the degree of diagenesis and oil generating potential of shales. Geochim Cosmochim Acta 40: 953966.CrossRefGoogle Scholar
Freed, R.L. and Peacor, D.R.. 1992. Diagenesis and the formation of authigenic illite-rich crystals in Gulf Coast shales: TEM study of clay separates. J Sediment Petrol 62: 220234.Google Scholar
Frey, M.. 1987. Very low-grade metamorphism of clastic sedimentary rocks. In: Frey, M., editor. Low temperature metamorphism. London: Blackie. p 958.Google Scholar
Guthrie, G.D. and Veblen, D.R.. 1989. High resolution transmission electron microscopy of mixed-layer illite/smectite: Computer simulations. Clays & Clay Miner 37: 111.CrossRefGoogle Scholar
Heling, D.. 1978. Diagenesis of illite in argillaceous sediments of the Rhine Graben. Clay Miner 13: 211219.CrossRefGoogle Scholar
Hower, J., Eslinger, E., Hower, M.E. and Perry, E.A.. 1976. Mechanism of burial metamorphism of argillaceous sediments: 1. Mineralogical and chemical evidence. Geol Soc Am Bull 87: 725737.2.0.CO;2>CrossRefGoogle Scholar
Islam, S., Hesse, R. and Chagnon, A.. 1982. Zonation of diagenesis and low-grade metamorphism in Cambro-Ordovician flysch of Gaspé Peninsula, Quebec Appalachians. Can Mineral 20: 155167.Google Scholar
Jennings, S. and Thompson, G.R.. 1986. Diagenesis of Plio-Pleistocene sediments of the Colorado River delta, Southern California. J Sediment Petrol 56: 8998.Google Scholar
Jiang, W.T., Essene, E.J. and Peacor, D.R.. 1990. Transmission electron microscopic study of coexisting pyrophyllite and muscovite: direct evidence for the metastability of illite. Clays & Clay Miner 38: 225240.CrossRefGoogle Scholar
Jiang, W.T. and Peacor, D.R.. 1993. Formation and modification of metastable intermediate Na-K mica, paragonite, and muscovite in hydrothermally altered metabasites from North Wales. Am Mineral 78: 782793.Google Scholar
Jiang, W.T., Peacor, D.R. and Buseck, P.R.. 1994. Chlorite Geother-mometry?—Contamination and Apparent Octaheddral Vacancies. Clays & Clay Miner 42: 593605.CrossRefGoogle Scholar
Kim, J.W., Peacor, D.R., Tessier, D. and Elsass, F.. 1995. A technique for maintaining texture and permanent expansion of smectite interlayers for TEM observations. Clays & Clay Miner 43: 5157.CrossRefGoogle Scholar
Kretz, R.. 1983. Symbols for rock forming minerals. Am Miner 68: 277279.Google Scholar
Kübler, B.. 1968. Evaluation quantitative du metamorphisme par la cristallinité de l'illite. Bull Centre Rech Pay-S.N.P.A. 2: 385397.Google Scholar
Lanson, B. and Champion, D.. 1991. The I/S-to-illite reaction in the late stage diagenesis. Am J Sci 291: 473506.CrossRefGoogle Scholar
Li, G., Peacor, D.R., Merriman, R.J. and Roberts, B.. 1994. The Diagenetic to Low-Grade Metamorphic Evolution of Matrix White Micas in the System Muscovite-Paragonite in a Mudrock from Central Wales, United Kingdom. Clays & Clay Miner 42: 369381.CrossRefGoogle Scholar
Lindgreen, H. and Hansen, P.L.. 1991. Ordering of illite-smectite in Upper Jurassic claystones from the North Sea. Clay Miner 26: 105125.CrossRefGoogle Scholar
López Munguira, A., Nieto, F., Sebastián, E. and Velilla, N.. 1991. The composition of phyllosilicates in Precambrian, low-grade-metamorphism, clastic rocks from the Southern Hesperian Massif (Spain) used as indicator to metamorphic conditions. Precambrian Res 53: 267279.CrossRefGoogle Scholar
MacEwan, D.M.C. and Wilson, M.J.. 1980. Interlayer and intercalation complexes of clay minerals. In: Brindley, G.W., Brown, G., editors. Crystal structures of clay minerals and their X-ray identification. London: Miner Soc. p 197248.CrossRefGoogle Scholar
Massone, H.J. and Schreyer, W.. 1987. Phengite geobarometry based on the limiting assemblage with K-feldspar phlogopite and quartz. Contr Mineral Petrol 96: 212224.CrossRefGoogle Scholar
Merriman, R.J. and Roberts, B.. 1985. A survey of white mica crystallinity and polytypes in pelitic rocks of Snowdonia and Llyn, North Wales. Miner Mag 49: 305319.CrossRefGoogle Scholar
Merriman, R.J., Roberts, B. and Peacor, D.R.. 1990. A transmision electron microscope study of white mica crystallite size distribution in a mudstone to slate transitional sequence, North Wales, U.K. Contr Mineral Petrol 106: 2740.CrossRefGoogle Scholar
Morse, J.W. and Casey, W.H.. 1988. Ostwald processes and mineral paragenesis in sediments. Am J Sci 288: 537560CrossRefGoogle Scholar
Nadeau, P.H., Wilson, J., McHardy, W. and Tait, J.M.. 1985. The conversion of smectite to illite during diagenesis: evidence from some illitic clays from bentonites and sandstones. Min Mag 49: 393400CrossRefGoogle Scholar
Nieto, F. and Sanchez Navas, A.. 1994. XRD/TEM comparative study on the physical meaning of white mica “cristallinity” index. Eur J Min 6: 611621.CrossRefGoogle Scholar
Noack, Y., Giroir, G. and Girard, J.P.. 1987. Chlorites as indicators of paleoenvironments. In: Rodriguez Clemente, R., Tardy, Y., editors. Geochemistry and mineral formation in the earth surface. Madrid: C.S.I.C. p 639652.Google Scholar
Peacor, D.R.. 1992. Diagenesis and low-grade metamorphism of shales and slates. In: Buseck, P., Ribbe, P.H., editors. Reviews in Mineralogy. Chelsea: Miner Soc Am. 27: 335380.Google Scholar
Perry, E. and Hower, J.. 1970. Burial diagenesis in Gulf coast pelitic sediments. Clays & Clay Miner 18: 165177.CrossRefGoogle Scholar
Powers, M.C.. 1967. Fluid release mechanisms in compacting marine mudrocks and their importance in oil exploration. A.A.P.G. Bull 51: 12401254.Google Scholar
Ramseyer, K. and Boles, J.R.. 1986. Mixed-layer illite/smectite minerals in Tertiary sandstones and shales, San Joaquin basin, California. Clays & Clay Miner 34: 115124.CrossRefGoogle Scholar
Reynolds, R.C.. 1980. Interstratified clay minerals. In: Brindley, G.W., Brown, G., editors. Crystal Structures of clay minerals and their X-ray identification. London: Miner Soc. p 249304.CrossRefGoogle Scholar
Shau, Y.H., Peacor, D.R. and Essene, E.J.. 1990. Corrensite and mixed-layer chlorite/corrensite in metabasalt from northern Taiwan: TEM/AEM, EMPA, XRD, and optical studies. Contrib Mineral Petrol 105: 123142.CrossRefGoogle Scholar
Shau, Y.H., Feather, M.E., Essene, E.J. and Peacor, D.R.. 1991. Genesis and solvus relations of submicroscopically intergrown paragonite and phengite in a blueschist from northern California. Contrib Mineral Petrol 106: 367378.CrossRefGoogle Scholar
Srodon, J. and Eberl, D.. 1984. Illite. In: Bailey, S.W., editor. Reviews in Mineralogy. Chelsea: Miner Soc Am. 13: 495544.Google Scholar
Suchecki, R.K., Perry, E.A. and Hubert, J.F.. 1977. Clay petrology of Cambro-Ordovician continental margin, Cow Head Klippe, Western Newfoundland. Clays & Clay Miner 25: 163170.CrossRefGoogle Scholar
Van Der Pluijm, B.A., Lee, J.H. and Peacor, D.R.. 1988. Analytical electron microscopy and the problem of potassium diffusion. Clays & Clay Miner 36: 498504.CrossRefGoogle Scholar
Yau, Y.C., Peacor, D.R. and McDowell, S.D.. 1987. Smectite-to-illite reactions in Salton Sea shales; a transmission and analytical electron microscopy study. J Sediment Petrol 57: 335342.Google Scholar