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The plagioclase, forsterite, diopside, liquid equilibrium in the system CaO-Na2O-MgO-Al2O3-SiO2

Published online by Cambridge University Press:  05 July 2018

G. M. Biggar  and
D. J. Humphries
G. M. Biggar
Affiliation:
Department of Geology, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JW
D. J. Humphries
Affiliation:
Department of Geology, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JW
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Abstract

Liquids in the system CaO-Na2O-MgO-Al2O3-SiO2 which crystallize plagioclase and forsterite, often with diopside and sometimes with spinel, were studied. The movement of the plagioclase-forsterite saturation surface to higher plagioclase contents as albite replaces anorthite, and the concurrent expansion of the forsterite and diopside primary fields, are documented. The maximum temperature of the liquid in equilibrium with plagioclase, diopside, and forsterite decreases as the anorthite to albite ratio decreases and as enstatite is added, and was experimentally determined over part of its range from 1278 to 113°C The decrease was not linear, being generally small even when 67 mole% albite was present, and thereafter, it must decrease rapidly to reach the values reported for the system albite-diopside-forsterite.

Type
Research Article
Information
Mineralogical Magazine , Volume 44 , Issue 335 , September 1981 , pp. 309 - 314
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1981

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References

Biggar, G. M. (1972). Mineral. Mag. 38, 768.Google Scholar
Biggar, G. M. and O'Hara, M. J. (1969a). Ibid. 37, 198.Google Scholar
Biggar, G. M. (1969b). Ibid. 1.Google Scholar
Cox, K. G., Bell, J. D., and Pankhurst, R. J. (1979). The interpretation of igneous rocks. George Allen & Unwin, London, 450 pp.CrossRefGoogle Scholar
Eggler, D. H. (1974). Am. J. Sci. 274, 297.CrossRefGoogle Scholar
Emslie, R. F. (1971). Carnegie Inst. Washington Yearb. 69, 148.Google Scholar
Humphries, D. J. (1972). Progress in Exptl. Petrol. 2nd Report. NERC London, Publication Series D, No. 2, p. 120.Google Scholar
Humphries, D. J. (1975). Phase equilibrium studies of some basalt-like compositions in the system CaO-MgO-Al2O3-SiO2-Na2O-Fe-O2. Thesis, University of Edinburgh.Google Scholar
Longhi, J. and Boudreau, A. E. (1980). Am. Mineral. 65, 563.Google Scholar
O'Hara, M. J. (1976). Progress in Exptl. Petrol. 3rd Report. NERC p. 103. London, Publication Series D, No. 6, 1976, pp. 103-26.Google Scholar
Presnall, D. C., Dixon, S. A., Dixon, J. R., Donnell, T. H., Brenner, N. L., Schrock, R. L., and Dycus, D. W. (1978). Contrib. Mineral. Petrol. 66, 203.CrossRefGoogle Scholar
Schairer, J. F. and Morimoto, N. (1959) Carnegie Inst. Washington Yearb. 58, 113.Google Scholar