Hostname: page-component-848d4c4894-cjp7w Total loading time: 0 Render date: 2024-06-13T11:44:59.744Z Has data issue: false hasContentIssue false
  • English
  • Français

The crystal morphology of plagioclase feldspar produced during isothermal supercooling and constant rate cooling experiments

Published online by Cambridge University Press:  05 July 2018

G. M. Corrigan
G. M. Corrigan*
Affiliation:
Department of Geology, University of Sheffield, Sheffield S1 3JD
Get access Rights & Permissions [Opens in a new window]

Abstract

The crystal morphology of plagioclase feldspar in seven mafic rocks has been studied by isothermal supercooling and constant rate cooling experiments at 1 atmosphere using the ‘wire-loop’ suspension method. There is a systematic variation in crystal morphology with supercooling (−ΔT), but the transitions between the different morphologies are gradual, and consecutive forms sometimes occur together. As −ΔT increases, the sequence of plagioclase morphology is generally laths → skeletal forms → fan spherulites. During isothermal supercooling the position of the plagioclase morphological fields is shown to be dependent on −ΔT, superheating (+ΔT), and also on time to a greater or lesser degree. Variations in melt composition and viscosity affect the position and slope of the boundaries of the fields. In the constant rate cooling experiments, the morphological type is dependent on the cooling rate and can be used to a limited extent as an indicator of the range of supercooling over which the first crystals nucleated and grew.

Type
Research Article
Information
Mineralogical Magazine , Volume 46 , Issue 341 , December 1982 , pp. 433 - 439
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1982

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.)

Footnotes

*

Present address: Meadow House, Hill House Road, St. Bees, Cumbria CA27 0BZ.

References

Corrigan, G. (1980) Unpub. Ph.D. thesis, Univ. of Sheffield.Google Scholar
Corrigan, G. (1982) Mineral. Mag. 46, 31–42.CrossRefGoogle Scholar
Donaldson, C. H. (1976) Contrib. Mineral. Petrol. 57, 187–213.CrossRefGoogle Scholar
Fenn, P. M. (1973) Unpub. Ph.D. thesis, Univ. of Stan¬ford, USA.Google Scholar
Gibb, F. G. F. (1974) Mineral. Mao. 39, 641–53.CrossRefGoogle Scholar
Hamilton, D. L., and Anderson, G. M. (1967) In Basalts, New York (Interscience), 445–82.Google Scholar
Lofgren, G. (1971a) J. Geophys. Res. 76, 563–548.CrossRefGoogle Scholar
Lofgren, G. (1971b) Geol. Soc. Am. Bull. 82, 111–24.CrossRefGoogle Scholar
Lofgren, G. (1973) Trans. Am. Geophys. Union. 54, 482.Google Scholar
Lofgren, G. (1974) Am. J. Sci. 274, 243–73.CrossRefGoogle Scholar
Lofgren, G. and Donaldson, C. H. (1975a) Trans. Am. Geophys. Union, 56, 468.Google Scholar
Lofgren, G. (1975b) Contrib. Mineral. Petrol. 49, 309–19.CrossRefGoogle Scholar
Moore, J. G., and Lockwood, J. P. (1973) Geol. Soc. Am. Bull. 84, 1–20.2.0.CO;2>CrossRefGoogle Scholar
Wyllie, P. J., and Drever, H. I. (1963) Trans. Roy. Soc. Edin. 65, 155–77.CrossRefGoogle Scholar