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Thickness Distributions and Evolution of Growth Mechanisms of NH4-Illite from The Fossil Hydrothermal System of Harghita Bãi, Eastern Carpathians, Romania

Published online by Cambridge University Press:  01 January 2024

Iuliu Bobos*
Affiliation:
Centre of Geology, Faculty of Sciences, University of Porto, Portugal
D. D. Eberl
Affiliation:
Emeritus Scientist, U.S. Geological Survey, 3215 Marine Street, Suite E127, Boulder, Colorado 80303-1066, USA
*
*E-mail address of corresponding author: ibobos@fc.up.pt

Abstract

The crystal growth of NH4-illite (NH4-I) from the hydrothermal system of Harghita Bãi (Eastern Carpathians) was deduced from the shapes of crystal thickness distributions (CTDs). The <2 mm and the <2-0.2 mm fractions of clay samples collected from the argillized andesite rocks consist of NH4-illite-smectite (I-S) interstratified structures (R1, R2, and R3-type ordering) with a variable smectite-layer content. The NH4-I-S (40-5% S) structures were identified underground in a hydrothermal breccia structure, whereas the K-I/NH4-I mixtures were found at the deepest level sampled (-110 m). The percentage of smectite interlayers generally decreases with increasing depth in the deposit. This decrease in smectite content is related to the increase in degree of fracturing in the breccia structure and corresponds to a general increase in mean illite crystal thickness. In order to determine the thickness distributions of NH4-I crystals (fundamental illite particles) which make up the NH4-I-S interstratified structures and the NH4-I/K-I mixtures, 27 samples were saturated with Li and aqueous solutions of PVP-10 to remove swelling and then were analyzed by X-ray diffraction. The profiles for the mean crystallite thickness (Tmean) and crystallite thickness distribution (CTD) of NH4-I crystallites were determined by the Bertaut-Warren-Averbach method using the MudMaster computer code. The Tmean of NH4-I from NH4-I-S samples ranges from 3.4 to 7.8 nm. The Tmean measured for the NH4-I/K-I mixture phase ranges from 7.8 nm to 11.7 nm (NH4-I) and from 12.1 to 24.7 nm (K-I).

The CTD shapes of NH4-I fundamental particles are asymptotic and lognormal, whereas illites from NH4-I/K-I mixtures have bimodal shapes related to the presence of two lognormal-like CTDs corresponding to NH4-I and K-I.

The crystal-growth mechanism for NH4-I samples was simulated using the Galoper code. Reaction pathways for NH4-I crystal nucleation and growth could be determined for each sample by plotting their CTD parameters on an α-ß2 diagram constructed using Galoper. This analysis shows that NH4-I crystals underwent simultaneous nucleation and growth, followed by surface-controlled growth without simultaneous nucleation.

Type
Article
Copyright
Copyright © The Clay Minerals Society 2013

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References

Aldega, A. and Eberl, D.D., 2005 Detrital illite crystals identified from crystallite thickness measurements in siliciclastic sediments American Mineralogist 90 15871596.CrossRefGoogle Scholar
Amelincks, S., 1952 La croissance helicoidale de cristaux du biotite Compte Rendu 234 971973.Google Scholar
Baronnet, A., 1982 Ostwald Ripening: The case of calcite and mica Estúdios Geologie 6 675685.Google Scholar
Baronnet, A., 1984 Growth kinetics of the silicates. A review of basic concepts Fortschritte der Mineralogie 62 187232.Google Scholar
Benjamin, J.R. and Cornell, C.A., 1970 Probability and Decision for Civil Engineers New York McGraw-Hill.Google Scholar
Bleahu, M. Boccaletti, M. Manetti, P. and Peltz, S., 1973 Neogene Carpathian Arc: A continental arc displaying the features of an “Island Arc” Journal of Geophysical Research 788/ 23 50255032.CrossRefGoogle Scholar
Blum, A., Nagy, K.L. and Blum, A., 1994 Determination of illite-smectite particle morphology using scanning force microscopy Scanning Probe Microscopy of Clay Minerals Bloomington, Indiana, USA The Clay Minerals Society 171202.Google Scholar
Bobos, I., 2000.The fossil hydrothermal system of Harghita Bãi, East Carpathians, Romania: Argillic alterationGoogle Scholar
Bobos, I., 2012 Characterization of smectite to NH4-illite conversion series in the fossil hydrothermal system of Harghita Bãi, East Carpathians, Romania American Mineralogist 97 962982.CrossRefGoogle Scholar
Bobos, I. and Ghergari, L., 1999 Conversion of smectite to ammonium illite in the hydrothermal system of Harghita Bãi, Romania: SEM and TEM investigations Geologica Carpathica 50 379387.Google Scholar
Bove, D.J. Eberl, D.D. McCarty, D.K. and Meeker, G.P., 2002 Characterization and modeling of illite crystal particles and growth mechanisms in a zoned hydrothermal deposit, Lake City, Colorado American Mineralogist 87 15461556.CrossRefGoogle Scholar
Brime, C. and Eberl, D.D., 2002 Growth mechanisms of lowgrade illites based on shapes of crystal thickness distributions Schweizeriche Mineralogische Petrographische Mitteilungen 82 203209.Google Scholar
Clauer, N. Liewig, N. and Bobos, I., 2010 K-Ar, δ18O and REE constraints on the genesis of ammonium illite from the Harghita Bai hydrothermal system, Romania Clay Minerals 45 393411.CrossRefGoogle Scholar
Drits, V. Eberl, D.D. and Środoń, J., 1998 XRD measurement of mean thickness, thickness distribution and strain for illite and illite-smectite crystallites by the Bertaut-Warren-Averbach technique Clays and Clay Minerals 46 3850.CrossRefGoogle Scholar
Dudek, T. and Środoń, J., 2003 Thickness distribution of illite crystals in shales. II: Origin of the distribution and the mechanism of smectite illitization in shales Clays and Clay Minerals 51 529542.CrossRefGoogle Scholar
Dudek, T. Środoń, J. Eberl, D.D. Elsass, F. and Uhlik, P., 2002 Thickness distribution of illite crystals in shales. I: X-ray diffraction vs. high resolution transmission electron microscopy measurements Clays and Clay Minerals 50 562577.CrossRefGoogle Scholar
Eberl, D.D., Rule, A. and Guggenheim, S., 2002 Determination of illite crystallite thickness distributions using X-ray diffraction, and the relation of the thickness to crystal growth mechanisms using MUDMASTER, GALOPER, and associated computer programs Teaching Clay Science, CMS Workshop Lectures Aurora, Colorado, USA The Clay Minerals Society 131142.Google Scholar
Eberl, D.D. and Środoń, J., 1988 Ostwald ripening and interparticle-diffraction effects for illite crystals American Mineralogist 73 13351345.Google Scholar
Eberl, D.D. Środoń, J. Lee, M. Nadeau, P. and Northrop, R.H., 1987 Sericite from the Silverton caldera: Correlation among structure, composition, origin and particle thickness American Mineralogist 72 914935.Google Scholar
Eberl, D.D. Środoń, J. Kralik, M. Taylor, B.E. and Peterman, Z.E., 1990 Ostwald Ripening of clays and metamorphic minerals Science 248 474477.CrossRefGoogle Scholar
Eberl, D.D. Drits, V. Środoń, J. and Nüesch, R., 1996.MudMaster: A program for calculating crystallite size distributions and strain from the shapes of X-ray diffraction peaks U.S. Geological Survey Open-File Report 96-171CrossRefGoogle Scholar
Eberl, D.D. Drits, V.A. and Środoń, J., 1998 Deducing crystal growth mechanisms for minerals from the shapes of crystal size distributions American Journal of Science 298 499533.CrossRefGoogle Scholar
Eberl, D.D. Nüesch, R. Šucha, V. and Tsipursky, S., 1998 Measurement of fundamental illite particle thicknesses by X-ray diffraction using PVP-10 intercalation Clays and Clay Minerals 46 8997.CrossRefGoogle Scholar
Eberl, D.D. Drits, V.A. and Środoń, J., 2000.User’s guide to GALOPER—a program for simulating the shapes of crystal size distributions and associated programs U.S. Geological Survey Open File ReportCrossRefGoogle Scholar
Eberl, D.D. Środoń, J. and Drits, V.A., 2003 Comment on “Evaluation of X-ray diffraction methods for determining the crystal growth mechanisms of clay minerals in mudstones, shales and slates,” by L.N. Warr and D.L. Peacor Schweizerische Mineralogische Petrographische Mitteilungen 83 349358.Google Scholar
Frank, F.C. (1949) The influence of dislocations on crystal growth: Discussions. Faraday Society, 5, 48.CrossRefGoogle Scholar
Hedenquist, J.W. and Lowenstern, J.B., 1994 The role of magmas in the formation of hydrothermal ore deposits Nature 370 519527.CrossRefGoogle Scholar
Higashi, S., 1982 Tobelite, a new ammonium dioctahedral mica Mineralogical Journal 11 138146.CrossRefGoogle Scholar
Inoue, A. and Kitagawa, R., 1994 Morphological characteristics of illitic clay minerals from a hydrothermal system American Mineralogist 79 700711.Google Scholar
Inoue, A. Utada, M. and Wakita, K., 1992 Smectite-to-illite conversion in natural hydrothermal systems Applied Clay Science 7 131145.CrossRefGoogle Scholar
Inoue, A. Velde, B. Meunier, A. and Touchard, G., 1988 Mechanism of illite formation during smectite-to-illite conversion in a hydrothermal system American Mineralogist 73 241249.Google Scholar
Jackson, M.L., 1975 Soil Chemical Analysis—Advanced Course Madison, Wisconsin, USA Published by the author.Google Scholar
Kitagawa, R., 1992 Surface microtopographies of pyrophyllite from the Shokozan area, Chugoku Province, southwest Japan Clay Science 8 285295.Google Scholar
Kitagawa, R., Churchman, J. Fitzpatrick, R.W. and Eggleton, R.A., 1995 Coarsening process of a hydrothermal sericite sample using surface microtopography and transmission electron microscopy techniques Clays Controlling the Environment Adelaide, Australia Proceedings of the International Clay Conference 249252.Google Scholar
Kitagawa, R. and Matsuda, T., 1992 Microtopography of regularly-interstratified mica and smectite Clays and Clay Minerals 40 114121.CrossRefGoogle Scholar
Komatsu, H. and Sunagawa, I., 1965 Surface structures of sphalerite crystals American Mineralogist 50 10461057.Google Scholar
Kotarba, M. and Środoń, J., 2000 Diagenetic evolution of crystallite thickness distribution of illitic material in Carpathian shales, studied by the Bertaut-Warren-Averbach XRD method (MudMaster computer program) Clay Minerals 35 383391.CrossRefGoogle Scholar
Krumbein, W.C. and Graybill, F.A., 1965 An Introduction to Statistical Models in Geology New York McGraw Hill Company.Google Scholar
Masterton, W.L. Slowinski, E.J. and Stanitski, C.L., 1981 Chemical Principles Philadelphia, Pennsylvania, USA Holt-Saunders International.Google Scholar
McHardy, W.J. Birnie, A.C., and Wilson, M.J., 1987 Scanning electron microscopy A Handbook of Determinative Methods in Clay Mineralogy Glasgow, UK Blackie 74208.Google Scholar
Meyer, C. Hemley, J.J., and Barnes, H.L., 1967 Wall-rock alteration Geochemistry of Hydrothermal Ore Deposits New York Holt, Rinehart, and Winston 166235.Google Scholar
Moore, D.M. and Reynolds, R.C., 1997 X-ray diffraction and the Identification and Analysis of Clay Minerals New York Oxford University Press.Google Scholar
Mystkowski, K. Środoń, J. and Elsass, F., 2000 Mean thickness and thickness distribution of smectite crystallites Clay Minerals 35 545557.CrossRefGoogle Scholar
Nadeau, P.H. Wilson, M.J. McHardy, W.J. and Tait, J.M., 1985 The conversion of smectite to illite during diagen-esis. Evidence from some illitic clays from bentonites and sandstones Mineralogical Magazine 49 393400.CrossRefGoogle Scholar
Peltz, S. Vâjdea, E. Balogh, K. and Pécskay, Z., 1987 Contributions to the chronological study of the volcanic processes in the Cãlimani and Harghita Mountains (East Carpathians, Romania) Compte Rendu de Institute de Geologie e Geofisique 72-73/ 1 323338.Google Scholar
Rãdulescu, D.P. and Sãndulescu, M., 1973 The plate-tectonics concept and the geological structure of the Carpathians Tectonophysics 16 155161.CrossRefGoogle Scholar
Rãdulescu, D.P. Peltz, S. and Stanciu, C., 1973.Neogene volcanism in the East Carpathians (Cãlimani-Gurghiu-Harghita Mts.) Guide to Excursion 2AB. Symposium: Volcanism and MetallogenesisGoogle Scholar
Reynolds, R.C., 1985 NEWMOD, a computer program for the calculation of one dimensional diffraction patterns of mixed layered clays Hanover, New Hampshire Published by the author.Google Scholar
Royden, L.H., 1988 Late Cenozoic tectonics of the Pannonian Basin System American Association Petroleum Geology Memoir 45 2728.Google Scholar
Sãndulescu, M., 1984 Geotectonics of Romania Bucharest Technical Publishing House.Google Scholar
Seghedi, I. Balintoni, I. and Szakacs, A., 1998 Interplay of tectonics and Neogene post-collisional magmatism in the intracarpathian area Lithos 45 483499.CrossRefGoogle Scholar
Seghedi, I. Downes, H. Szakacs, A. Mason, P.R.D. Thirlwall, M.F. Rosu, E. Pécskay, Z. Marton, E. and Panaiotu, C., 2004 Neogene-Quaternary magmatism and geodynamics in the Carpathian—Pannonian region: a synthesis Lithos 72 117146.CrossRefGoogle Scholar
Sillitoe, R.H., 2010 Porphyry copper systems Economic Geology 105 341.CrossRefGoogle Scholar
Środoń, J. Eberl, D.D. and Drits, V., 2000 Evolution of fundamental particle size during illitization of smectite and implications for reaction mechanism Clays and Clay Minerals 48 446458.CrossRefGoogle Scholar
Stanciu, C., 1984 Hypogene alteration of Neogene volcanism of the East Carpathians Annuare de Institute de Geologique e Geofisique LXIV 182193.Google Scholar
Sunagawa, I., 1960 Mechanism of crystal growth, etching, and twin formation of hematite Mineralogical Journal 3 5989.CrossRefGoogle Scholar
Sunagawa, I., 1961 Step height of spirals on natural hematite crystals American Mineralogist 46 12161226.Google Scholar
Sunagawa, I., 1962 Mechanism of growth of hematite American Mineralogist 47 11391155.Google Scholar
Sunagawa, I., 1964 Growth spirals on phlogopite crystals American Mineralogist 49 14271434.Google Scholar
Sunagawa, I. and Koshino, , 1975 Growth spirals on kaolin group minerals American Mineralogist 60 401412.Google Scholar
Szakacs, A. and Seghedi, I., 1995 The Cãlimani-Gurghiu-Harghita volcanic chain, Eastern Carpathians, Romania: volcanological features Acta Vulcanologica 7 145153.Google Scholar
Verma, A.R. (1956) A phase contrast microscopic study of the surface structure of blende crystals. Mineralogical Magazine, 31, 136.CrossRefGoogle Scholar
Warr, N.L. and Nieto, F., 1998 Crystallite thickness and defect density of phyllosilicates in low-temperature metamorphic pelites: a TEM and XRD study of clay-mineral crystallinity index standards The Canadian Mineralogist 36 14531474.Google Scholar
Williams, L.B. and Hervig, R.L., 2006 Crystal size dependence of illite-smectite isotope equilibration with changing fluids Clays and Clay Minerals 54 531540.CrossRefGoogle Scholar