Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-23T21:19:04.842Z Has data issue: false hasContentIssue false

Non-cylindrical folds, linear structures in the X direction and mylonite developed during translation of the Caledonian Kalak Nappe Complex of Finnmark

Published online by Cambridge University Press:  01 May 2009

S. Rhodes
Affiliation:
Geology Department, University College, Cardiff, Wales
R. A. Gayer
Affiliation:
Geology Department, University College, Cardiff, Wales

Summary

Structural evidence from the Kalak Nappe Complex suggests the operation of layer parallel shearing stresses during the translation of the nappes. A simple shear model invoking irregular areas of high cohesion within individual layer boundaries is used to explain the development of both intra-folial, cylindrical and non-cylindrical folds and a regular zone of syn-folding blasto-mylonite at the base of the nappe(s). Fold hinges that are initially developed parallel to the Y axis of the strain ellipsoid during layer parallel shearing may be rotated towards the X direction as a result of large strains concentrated at points of high cohesion within the layering boundaries.

Type
Articles
Copyright
Copyright © Cambridge University Press 1977

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.)

References

Anderson, E. M. 1948. On lineation and petrofabric structure and the shearing movement by which they have been produced. Q. Jl geol. Soc. Lond. 104, 99132.CrossRefGoogle Scholar
Bryant, B. & Reed, J. C. 1969. Significance of lineation and minor folds near major thrust faults in the southern Appalachian and the British and Norwegian Caledonides. Geol. Mag. 106, 412–29.CrossRefGoogle Scholar
Brynhi, I. 1962. Structural analysis of the Grøneheia area, Eikefjord, western Norway. Norsk. geol. Tidsskr. 42, 331–69.Google Scholar
Christie, J. M. 1960. Mylonite rocks of the Moine Thrust-Zone in the Assynt region, northwest Scotland. Trans. Edinb. geol. Soc. 18, 7993.CrossRefGoogle Scholar
Christie, J. M. 1963. The Moine Thrust-Zone in the Assynt Region, northwest Scotland. University of California publications in Geological Sciences, 40(byes), 345440.Google Scholar
Escher, A. & Watterson, J. 1974. Stretching fabrics, folds and crustal shortening. Tectonophysics 22, 223–31.CrossRefGoogle Scholar
Flinn, D. 1962. On the symmetry principle and the deformation ellipsoid. Geol. Mag. 102, 3645.CrossRefGoogle Scholar
Gayer, R. A., Powell, D. B. & Rhodes, S. (in the press). Deformation against metadolerite dykes in the Caledonian Kalak Nappe Complex of Finnmark.Google Scholar
Gayer, R. A. & Roberts, J. D. 1973. Stratigraphic review of the Finnmark Caledonides, with possible tectonic implications. Proc. Geol. Assoc. Lond. 84, 405–28.CrossRefGoogle Scholar
Gee, D. G. 1975 a. A tectonic model for the central part of the Scandinavian Caledonides. Am. J. Sci. 275A, 468515.Google Scholar
Gee, D. G. 1975 b. A Geotraverse through the Scandinavian Caledonides, Ostersund to Trondheim. Sveriges geol. Unders. C 717, 166.Google Scholar
Harland, W. B. & Bayly, M. B. 1958. Tectonic regimes. Geol. Mag. 95, 89104.CrossRefGoogle Scholar
Hooper, P. R. 1968. The a lineation and the trend of the Caledonides of northern Norway. Norsk. geol. Tidsskr. 48, 261–8.Google Scholar
Johnson, M. R. W. 1967. Mylonite zones and mylonite banding. Nature, Lond. 213, 246–7.CrossRefGoogle Scholar
Knill, J. L. & Knill, D. C. 1958. Some discordant fold structures from the Dalradian of Craignish, Argyll and Rosguile, Co. Donegal. Geol. Mag. 95, 497510.CrossRefGoogle Scholar
Kvale, A. 1953. Linear structures and their relation to movement in the Caledonides of Scandinavia. Q. Jl geol. Soc. Lond. 109, 5174.CrossRefGoogle Scholar
Lapworth, C. 1885. The Highland controversy in British Geology: its causes, course and consequences. Nature, Lond. 32, 558–9.Google Scholar
Lindstrom, M. 1958. Tectonic transports in three small areas in the Caledonides of Swedish Lapland. Lunds Univ. Arsskr. N.F. Avd. 2,54(3yes), 185.Google Scholar
Lindstrom, M. 1961. Beziehungen zwischen Kleinfaltenvergenzen und anderen Gefugemerkmalen in den Kaledoniden Skandinaviens. Geol. Rdsch. 51, 144–80.CrossRefGoogle Scholar
Phillips, F. C. 1937. A fabric study of some Moine schists and associated rocks. Q. JI geol. Soc. Lond. 43,581620.CrossRefGoogle Scholar
Ramberg, H. 1967. Gravity, deformation and the earth's crust. Academic Press, London.Google Scholar
Ramsay, J. G. 1962. The geometry and mechanics of formation of ‘similar’ type folds. J. Geol. 70, 309–27.CrossRefGoogle Scholar
Ramsay, J. G. 1967. Folding and Fracturing of Rocks. London: McGraw-Hill.Google Scholar
Ramsay, D. M. & Sturt, B. A. 1973. An analysis of non-cylindrical and incongruous fold pattern from the Eocambrian rocks of Soroy, Northern Norway. 1. Non-cylindrical, incongruous and abberrant folding. Tectonophysics 18, 81107.CrossRefGoogle Scholar
Roberts, D. 1974. Hammerfest: Beskrivelse til det 1:25,000 berggrunns geologike kart. Norg. geol. Unders. 301, 161.Google Scholar
Sanderson, D. J. 1973. The development of fold axes oblique to the regional trend. Tectonophysics 16, 5570.CrossRefGoogle Scholar
Strand, T. & Kulling, O. 1972. Scandinavian Caledonides. London: Wiley-Interscience.Google Scholar
Stromberg, A. 1961. On the Tectonics of the Caledonides in the South-western Part of the County of Jamtland, Sweden. Bull. geol. Instn Upsala 39, 192.Google Scholar
Turner, F. J. 1957. Lineation, symmetry and internal movement in monoclinic tectonite fabrics. Bull. geol. Soc. Am. 68, 118CrossRefGoogle Scholar
Turner, F. J. & Weiss, L. E. 1963. Structural Analysis of Metamorphic Tectonites. New York: McGraw-Hill.Google Scholar
Voll, G. 1960. New work on petrofabrics. Lpool Mnchr geol. J. 2 (3yes), 503–67.CrossRefGoogle Scholar
Williams, G. D. (in the press). Rotation of contemporary folds into the X direction during overthrust processes in Laksefjord, Finnmark. Tectonophysics.Google Scholar
Williams, G. D., Rhodes, S., Powell, D. B., Passe, C. R., Noake, S. & Gayer, R. A. 1976. A revised tectonostratigraphy of the Kalak Nappe Complex in Central Finnmark. Norg. geol. Unders. 324, 4762.Google Scholar
Zeck, H. P. 1974. Cataclastites, hemiclastites, holoclastites, blasto-ditto and myloblastites — cataclastic rocks. Am. J. Sci. 274, 1064–73.CrossRefGoogle Scholar