Dislocations and voids in pyroxene from a low-temperature eclogite: Mechanism of eclogite formation
A transmission electron microscope study of dislocations and imperfections in omphacites of a low-temperature California eclogite has revealed a dislocation array related to a continuous creep phenomenon. Structures are appropriate to a combination of deformation and annealing processes similar to those observed in the hot working of some metals. The study has revealed the presence of voids or possible fluid inclusions which may indicate that the basalt to eclogite reaction was catalysed by a fluid phase which must have had a very low partial pressure of water.
KeywordsElectron Microscope Transmission Electron Microscope Partial Pressure Mineral Resource Microscope Study
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- Barber, D. J.: Thin foils of non-metals made for electron microscopy by sputter-etching. J. Materials Sci.5, 1–8 (1970)Google Scholar
- Bearth, P.: Über Eklogite, Glaukophanschiefer und metamorphe Pillow-laven. SMPM39, 267–286 (1959)Google Scholar
- Champness, P. E.: Speculation on an order-disorder transformation in omphacite. Am. Mineralogist58, 540–542 (1973)Google Scholar
- Champness, P. E., Lorimer, G. W.: An electron microscopic study of lunar pyroxene. Contr. Mineral. and Petrol.33, 171–183 (1971)Google Scholar
- Fry, N., Fyfe, W. S.: Eclogites and water pressure. Contr. Mineral. and Petrol.24, 1–6 (1969)Google Scholar
- Fry, N., Fyfe, W. S.: On the significance of the eclogite facies in alpine metamorphism. Verb. Geol. B-A, 257–265 (1971)Google Scholar
- Gilluly, J.: Plate tectonics and magmatic evolution. Geol. Soc. Am. Bull.82, 2383–2396 (1971)Google Scholar
- Griggs, D. T.: Hydrolytic weakening of quartz and other silicates. Geophys. J.14, 19–31 (1967)Google Scholar
- Lorimer, G. W., Champness, P. E.: Combined electron microscopy and analysis of an orthopyroxene. Am. Mineralogist58, 243–248 (1973)Google Scholar
- Lorimer, G. W., Champness, P. E., Spooner, E. T. C.: Dislocation distributions in naturally deformed omphacite and albite. Nature Phys. Sci.239, 108–109 (1972)Google Scholar
- Jonas, J. J., Sellars, C. M., McG. Tegart, W. J.: Strength and structure under hot-working conditions. Metals Rev.130, 1–24 (1969)Google Scholar