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The Geometry of Conjugate Fold Systems

Published online by Cambridge University Press:  01 May 2009

John G. Ramsay
Affiliation:
Department of Geology, Imperial College, London, S.W. 7.

Abstract

Conjugate shear fold systems are often developed when brittle laminated rocks are subjected to stress. These structures relationship of the principal axes of stress to the surface being folded. Within first order shear zones conjugate second order shear folds may be developed as a result of reorientation of the stress axes in these zones.

The axes of both first and second order conjugate shear folds may form at any angle to the principal stress axes and to the direction of movement within the shear zones. The principal axes of stress are most reliably determined from the orientation of the axial planes of the first order conjugate folds.

Type
Articles
Copyright
Copyright © Cambridge University Press 1962

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References

REFERENCES

Anderson, E. M., 1951. The dynamics of faulting. 2nd Edn. Edinburgh.Google Scholar
Billings, M. P., 1942. Structural geology. New York.Google Scholar
Darton, N. H., 1940. Some structural features of the Northern Coal Basin, Pennsylvania. Prof. Pap. U.S. geol. Surv., 193.Google Scholar
Greenly, E., 1919. The Geology of Anglesey. Mem. geol., G.B.Google Scholar
Johnson, M. R. W., 1956. Conjugate fold systems in the Moine thrust zone in the Lochcarron and Coulin Forest areas of Wester Ross. Geol. Mag., 93, 345350.CrossRefGoogle Scholar
McKinstry, H. E., 1953. Shears of the second order. Amer. J. Sci., 251, 401414.CrossRefGoogle Scholar
Moody, J. D., and Hill, M. J., 1956. Wrench fault tectonics. Bull. geol. Soc. Amer., 67, 12071246.CrossRefGoogle Scholar
Nevtn, C. M., 1936. Principles of structural geology. New York.Google Scholar
Sherbon Hills, E., 1940. Outlines of structural geology. London.Google Scholar
Sitter, L. U. De, 1956. Structural geology. London.Google Scholar
Sitter, L. U. De, 1958. Boudins and parasitic folds in relation to cleavage and folding. Geol. en Mijnb., 20, 277286.Google Scholar
Weiss, L. E., 1955. Fabric analysis of a triclinic tectonite and its bearing upon the theory of flow in rocks. Amer. J. Sci., 253, 225236.CrossRefGoogle Scholar
Weiss, L. E., and Paterson, M. S., 1961. Symmetry concepts in the structural analysis of deformed rocks. Bull. geol. Soc. Amer., 2, 841882.Google Scholar