Hostname: page-component-7c8c6479df-xxrs7 Total loading time: 0 Render date: 2024-03-29T08:14:09.344Z Has data issue: false hasContentIssue false

Microscopy and Microanalysis of Corona Textures in Eclogitic Greenschists from the Eastern Alps, Austria

Published online by Cambridge University Press:  14 March 2018

Robert Sturm*
Affiliation:
Salzburg, Austria

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Metamorphic rocks formed under conditions of high temperature (>600°C) and high lithological pressure (>1 GPa) and being subject to a subsequent tectonic uplift commonly include a remarkable number of fascinating mineral textures. One type of these well known and extensively described high-grade metamorphic textures are the so-called corona structures or reaction rims which, by definition, are primarily based on metamorphic reactions that cause the formation of concentric layers of new mineral phases separating an older and unstable mineral core from a newer and equally unstable mineral matrix. In other words, corona structures in metamorphic rocks preserve evidence of changes in the environmental conditions (temperature, pressure, fugacity of H2O) experienced by the rock during its tectonometamorphic history.

Type
Research Article
Copyright
Copyright © Microscopy Society of America 2008

References

(1) Foster, C. T. (1986): Thermodynamic models of reactions involving garnet in a sillimanite/staurolite schist. Min. Mag. 50, 427-439.CrossRefGoogle Scholar
(2) Foster, C. T. (1999): Forward modelling of metamorphic trextures. Can. Min. 37, 415-429.Google Scholar
(3) Griffin, W. L., & Heier, K. S. (1973): Petrological implications of some corona structures. Lithos 6, 315-335.Google Scholar
(4) Dachs, E., & Proyer, A. (2001): Relics of high-pressure metamorphism from the Grossglockner region, Hohe Tauern, Austria: Paragenetic evolution and PT-paths of retrogressed eclogites. Eu. J. Min. 13, 67-86.Google Scholar
(5) Sturm, R., Dachs, E., & Kurz, W. (1997): Untersuchung von Hochdruckrelikten in Grüngesteinen des Großglockner-Gebietes (zentrales Tauernfenster, Österreich): Erste Ergebnisse. Zentralbl. Geol. Paläontol. 3/4, 345-363.Google Scholar
(6) Sturm, R. (2003): Die Granate in eklogitischen Reliktgesteinen des zentralen Tauernfensters (Penninikum, Ostalpen): Chemismus, Zonierung und Reaktionsgefüge. Carinthia II 113, 515-526.Google Scholar
(7) Carswell, D. A. (1990): Eclogite Facies Rocks. Blackie and Son Ltd., Glasgow, London.Google Scholar
(8) Selverstone, J. (1985): Petrologic constraints on imbrication, metamorphism and uplift in the SW Tauern Window, Eastern Alps. Tectonics 4, 687-704.CrossRefGoogle Scholar