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Mylonite-dominated footwall geometry in a shear zone, central Pyrenees

Published online by Cambridge University Press:  01 May 2009

C. W. Passchier
C. W. Passchier
Affiliation:
Department of Geology, University College of Swansea, Singleton Park, Swansea SA2 8PP, U.K.
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Abstract

A major ductile shear zone in the gneissic core of the Saint-Barthélemy Massif, central Pyrenees, is characterized by an asymmetric shear strain profile defined as mylonite-dominated footwall geometry. The shear zone is part of a low angle fault system in the massif which caused thinning of a sequence of lithologic units and isograds. The shear zone is interpreted as a low angle normal fault zone of probably Cretaceous age, predating Alpine crustal shortening in the central Pyrenees.

Type
Articles
Information
Geological Magazine , Volume 121 , Issue 5 , September 1984 , pp. 429 - 436
Copyright
Copyright © Cambridge University Press 1984

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References

Boillot, G. 1983. North Pyrenean zone: a Mesozoic passive margin shortened during Eocene. Abstracts Pyrenees Workshop, Cambridge.Google Scholar
Butler, R. W. H. 1982. The terminology of structure in thrust belts. Journal of Structural Geology 4, 239–45.CrossRefGoogle Scholar
Choukroune, P. & Mattauer, M. 1978. Tectonique des plaques et Pyrénées. Bulletin Société géologique de France 20, 689–700.CrossRefGoogle Scholar
Christie, J. M. 1963. Moine thrust zone in the Assynt region of NW Scotland. University of California Publications of Geological Science 40, 345–440.Google Scholar
Coward, M. P. 1980. The Caledonian thrust and shear zones of NW Scotland. Journal of Structural Geology 2, 11–19.CrossRefGoogle Scholar
Crittenden, M. D., Coney, P. J. & Davis, G. H. 1980. Cordilleran metamorphic core complexes. Memoir of the Geological Society of America 153.CrossRefGoogle Scholar
Davis, G. H. 1983. Shear zone model for the origin of metamorphic core complexes. Geology 11, 342–7.2.0.CO;2>CrossRefGoogle Scholar
Debroas, E. J. 1978. Evolution de la fosse du flysch ardoisier de l'Albien supérieur au Sénonien inférieur. Bulletin Société géologique de France 20, 639–48.CrossRefGoogle Scholar
Debroas, E. J., Médiavilla, F. & Souquet, P. 1978. La zone de failles transcurrente de Bigorre dans la région de Lourdes et de Bagnères. Bulletin Société géologique de France 20, 631–8.CrossRefGoogle Scholar
Déramond, J., Graham, R. H. & Hossack, J. R. 1983. Restored sections in the Western Pyrenees. Abstracts Pyrenees Workshop, Cambridge.Google Scholar
Dubois, P. & Seguin, J. C. 1978. Les flysch crétacé et éocène de la zone commingeoise et leur environnement. Bulletin Société géologique de France 20, 657–71.CrossRefGoogle Scholar
Elliott, D. & Johnson, M. R. W. 1980. Structural evolution in the northern part of the Moine thrust belt. NW Scotland. Transactions of the Royal Society of Edinburgh 71, 69–96.CrossRefGoogle Scholar
Grocott, J. 1977. The relationship between Precambrian shear belts and modern fault systems. Journal of the Geological Society of London 133, 257–62.CrossRefGoogle Scholar
Hossack, J. R. 1983. A cross-section through the Scandinavian Caledonides constructed with the aid of branchline maps. Journal of Structural Geology 5, 103–13.CrossRefGoogle Scholar
Jaffrezo, M. & Obert, D. 1978. Les Pyrénées. Bulletin Société géologique de France 20, 587–629.CrossRefGoogle Scholar
Malzac, J. & Rousseau, A. 1982. Gravimétrie des Pyrénées Ariégoises. Bulletin Société géologique de France 24, 739–53.CrossRefGoogle Scholar
McCaig, A. M. & Miller, J. 1983. Alpine age of mylonites on the Merens Fault, central Axial Zone, Pyrenees. Abstracts Pyrenees Workshop, Cambridge.Google Scholar
Passchier, C. W. 1982 a. Pseudotachylyte and the development of ultramylonite bands in the Saint-Barthélemy Massif, French Pyrenees. Journal of Structural Geology 4, 69–79.CrossRefGoogle Scholar
Passchier, C. W. 1982 b. Mylonitic deformation in the Saint–Barthélemy Massif, French Pyrenees. GUA Papers of Geology No. 16.Google Scholar
Passchier, C. W. 1983. The reliability of asymmetric c-axis fabrics of quartz to determine sense of vorticity. Tectonophysics 99, T9–T18.CrossRefGoogle Scholar
Passchier, C. W. in press. The generation of ductile and brittle shear bands along a low angle mylonite zone, French Pyrenees. Journal of Structural Geology 6.Google Scholar
Poirier, J. P. 1980. Shear localization and shear instability in materials in the ductile field. Journal of Structural Geology 2 135–42.CrossRefGoogle Scholar
Seguret, M. 1972. Etude tectonique des nappes et séries décollees de la partie centrale du versant sud des Pyrénées. Série Géologique Structurale 2, Montpellier.Google Scholar
Sibson, R. H. 1977. Fault rocks and fault mechanisms. Journal of the Geological Society of London 133, 191–213.CrossRefGoogle Scholar
Sibson, R. H. 1978. Fault rocks and structure as indicators of shallow earthquake source processes. Proceedings of Conference ‘Analysis of actual fault zones in bedrock’. U.S. Geological Survey, 276–303.Google Scholar
Sibson, R. H. 1983. Continental fault structure and the shallow earthquake source. Journal of the Geological Society of London 140, 741–67.CrossRefGoogle Scholar
Sibson, R. H., White, S. H. & Atkinson, B. K. 1981. Structure and distribution of fault rocks in the Alpine fault zone, New Zealand. Geological Society of London Special Publications 9, 197–210.CrossRefGoogle Scholar
Soula, J. C. 1982. Characteristics and mode of emplacement of gneiss domes and plutonic domes in central-eastern Pyrenees. Journal of Structural Geology 4, 313–42.CrossRefGoogle Scholar
Tullis, J., Snoke, A. W. & Todd, V. R. 1982. Significance and petrogenesis of mylonitic rocks. Geology 10, 227–30.2.0.CO;2>CrossRefGoogle Scholar
Vielzeuf, D. & Kornprobst, J. 1984. Crustal splitting and the emplacement of Pyrenean Iherzolites and granulites. Earth and Planetary Science letters 67, 87–96.CrossRefGoogle Scholar
Vissers, R. L. M. 1983. The structure of the western Aston Massif. Abstracts Pyrenees Workshop, Cambridge.Google Scholar
Wernicke, B. & Birchfiel, B. C. 1982. Modes of extensional tectonics. Journal of Structural Geology 4, 105–15.CrossRefGoogle Scholar
White, S. H., Burrows, S. E., Carreras, J., Shaw, N. D. & Humphreys, F. J. 1980. On mylonites in ductile shear zones. Journal of Structural Geology 2, 175–87.CrossRefGoogle Scholar
Wickham, S. M. 1983. Granite petrogenesis in the Trois Seigneurs Massif, Eastern Pyrenees. Abstracts Pyrenees Workshop, Cambridge.Google Scholar
Williams, G. & Fischer, M. 1983. Geometry of Alpine deformation in central Pyrenees. Abstracts Pyrenees Workshop, Cambridge.Google Scholar
Zwart, H. J. 1954. La géologie du Massif du St. Barthélemy. Leidse geologische Mededelingen 18, 1–228.Google Scholar
Zwart, H. J. 1979. The geology of the central Pyrenees. Leidse Geologische Mededelingen 50, 1–74.Google Scholar