Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-18T22:09:29.395Z Has data issue: false hasContentIssue false

The effects of composition upon the high-pressure behaviour of amphiboles: compression of gedrite to 7 GPa and a comparison with anthophyllite and proto-amphibole

Published online by Cambridge University Press:  05 July 2018

F. Nestola*
Affiliation:
Dipartimento di Geoscienze, Università di Padova, via Gradenigo 6, 35131 Padova, Italy CNR Istituto di Geoscienze e Georisorse, UOS Padova, via Gradenigo 6, 35131 Padova, Italy
D. Pasqual
Affiliation:
Dipartimento di Geoscienze, Università di Padova, via Gradenigo 6, 35131 Padova, Italy
M. D. Welch
Affiliation:
Department of Mineralogy, The Natural History Museum, Cromwell Road, London SW7 5BD, UK
R. Oberti
Affiliation:
CNR Istituto di Geoscienze e Georisorse, UOS Pavia, via Ferrata 1, 27100 Pavia, Italy
*

Abstract

A single-crystal X-ray diffraction study of a sample of natural gedrite from North Carolina, USA, with the crystal-chemical formula ANa0.47B(Na0.03Mg0.97Fe0.942+Mn0.02Ca0.04)C(Mg3.52Fe0.282+Al1.15Ti0.054+)T(Si6.31Al1.69)O22W(OH)2, up to a maximum pressure of 7 GPa, revealed the following bulk and axial moduli and their pressure derivatives: K0T = 91.2(6) GPa [K0T' = 6.3(2)]; K0T(a) = 60.5(6) GPa [K0T(a)' = 6.1(2)]; K0T(b) = 122.8(2.6) GPa [K0T(b)' = 5.7(8)]; K0T (c) = 119.7(1.5) GPa [K0T(c)' = 5.1(5)]. Gedrite has a much higher bulk modulus than anthophyllite (66 GPa) and proto-amphibole (64 GPa). All of the three axial moduli of gedrite are higher than those of these two other orthoamphiboles. The greater stiffness of gedrite along [100] is due to its high ANa content, which is almost zero in anthophyllite and proto-amphibole. The much greater stiffness parallel to the (100) plane of gedrite compared with the two other amphiboles is probably due to its high CAl content. A comparison is made with published data available for orthorhombic B(Mg, Mn, Fe) and monoclinic BCa amphiboles to identify correlations between crystal-chemistry and compressibility in amphiboles.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2012

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

Angel, RJ. (2000) Equations of State. Pp. 3539 in: High-temperature and high-pressure crystal chemistry (R.M. Hazen and R.T. Downs, editors). Reviews in Mineralogy and Geochemistry, 41. Mineralogical Society of America, Washington DC and the Geochemical Society, St Louis, Missouri, USA.CrossRefGoogle Scholar
Angel, RJ. and Finger, L.W. (2011) SINGLE: a program to control single-crystal diffractometers. Journal of Applied Crystallography, 44, 247251.CrossRefGoogle Scholar
Angel, R.J., Allan, D.R., Miletich, R. and Finger, L.W. (1997) The use of quartz as an internal pressure standard in high-pressure crystallography. Journal of Applied Crystallography, 39, 461466.CrossRefGoogle Scholar
Angel, R.J., Downs, R.T. and Finger, L.W. (2000) High-temperature—high-pressure diffractometry. Pp. 247251 in: High-temperature and High-pressure Crystal Chemistry (R.M. Hazen and R.T. Downs, editors). Reviews in Mineralogy and Geochemistry, 41. Reviews in Mineralogy and Geochemistry, 41. Mineralogical Society of America, Washington DC and the Geochemical Society, St Louis, Missouri, USA.CrossRefGoogle Scholar
Angel, R.J., Bujak, M., Zhao, J., Gatta, G.D. and Jacobsen, S.D. (2007) Effective hydrostatic limits of pressure media for high-pressure crystallographic studies. Journal of Applied Crystallography, 40, 2632.CrossRefGoogle Scholar
Birch, F. (1947) Finite elastic strain of cubic crystals. Physical Review, 71, 809824.CrossRefGoogle Scholar
Birch, F. (1978) Finite strain isotherm and velocities for single-crystal and polycrystalline NaCl at high pressure and 300 K. Journal of Geophysical Research, 83, 12571268.CrossRefGoogle Scholar
Comodi, P., Mellini, M., Ungaretti, L. and Zanazzi, P.F. (1991) Compressibility and high-pressure structure refinement of tremolite, pargasite and glaucophane. European Journal of Mineralogy, 3, 485499.Google Scholar
Comodi, P, Boffa Ballaran, T., Zanazzi, P.F., Capalbo, C, Zanetti, A. and Nazzareni, S. (2010) The effect of oxo-component on the high-pressure behavior of amphiboles. American Mineralogist, 95, 10421051.Google Scholar
Graham, CM. and Navrotsky, A. (1986) Thermochemistry of the tremolite-edenite amphi-boles using fluorine analogs, and applications to amphibole-plagioclase-quartz. Contributions to Mineralogy and Petrology, 93, 1832.Google Scholar
Hawthorne, F.C., Schindler, M., Abdu, Y., Sokolova, E., Evans, B.E. and Ishida, K. (2008) The crystal-chemistry of gedrite-group amphiboles. II. Stereochemistry and chemical relations. Mineralogical Magazine, 72, 731745.CrossRefGoogle Scholar
Miletich, R., Allan, D.R and Kuhs, W.F. (2000) High-pressure single-crystal techniques. Pp. 445519 in: High-temperature and High-pressure Crystal Chemistry (RM. Hazen and RT. Downs, editors). Reviews in Mineralogy and Geochemistry, 41. Mineralogical Society of America, Washington DC and the Geochemical Society, St Louis, Missouri, USA.CrossRefGoogle Scholar
Nestola, F., Boffa Ballaran, T., Tribaudino, M. and Ohashi, H. (2005) Compressional behaviour of CaNiSi2O6 clinopyroxene: bulk modulus systematics and cation type in clinopyroxenes. Physics and Chemistry of Minerals, 32, 222227.CrossRefGoogle Scholar
Nestola, F., Boffa Ballaran, T., Liebske, C, Bruno, M. and Tribaudino, M. (2006) High-pressure behaviour along the jadeite NaAlSi2O6—aegirine NaFeSi2O6solid solution up to 10 GPa. Physics and Chemistry of Minerals, 33, 417425.CrossRefGoogle Scholar
Pawley, A.R, Graham, CM. and Navrotsky, A. (1990) Tremolite-richterite amphiboles: synthesis, compositional and structural characterization, and thermochemistry. American Mineralogist, 78, 2335.Google Scholar
Schindler, M., Sokolova, E., Abdu, Y., Hawthorne, F.C., Evans, B.E. and Ishida, K. (2008) The crystal-chemistry of the gedrite-group amphiboles. I. Crystal structure and site populations. Mineralogical Magazine, 72, 703730.CrossRefGoogle Scholar
Welch, M.D., Camara, F., Della Ventura, G and Iezzi, G (2007) Non-ambient in situ studies of amphiboles. Pp. 223260 in: Amphiboles: Crystal Chemistry, Occurrence, and Health Issues (F.C. Hawthorne, R. Oberti and G Della Ventura, editors). Reviews in Mineralogy and Geochemistry, 67. Mineralogical Society of America, Washington DC and the Geochemical Society, St Louis, Missouri, USA.CrossRefGoogle Scholar
Welch, M.D., Camara, F. and Oberti, R. (2011a) Thermoelasticity and high-T behaviour of antho-phyllite. Physics and Chemistry of Minerals, 38, 321334.CrossRefGoogle Scholar
Welch, M.D., Gatta, GD. and Rotiroti, N. (2010) The high-pressure behavior of orthorhombic amphiboles. American Mineralogist, 96, 623630.CrossRefGoogle Scholar
Zanazzi, P.F., Nestola, F., and Pasqual, D. (2010) Compressibility of protoamphibole: a high-pressure single-crystal diffraction study of protomangano-ferro-anthophyllite. American Mineralogist, 95, 17581764.CrossRefGoogle Scholar
Zema, M., Welch, M.D. and Oberti, R (2012) High-T behaviour of orthorhombic amphiboles: thermoelasticity, cation site-exchange and dehydrogenation in gedrite. Contributions to Mineralogy and Petrology, 163, 923937.Google Scholar