Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-22T06:08:47.676Z Has data issue: false hasContentIssue false
  • English
  • Français

Tectonic Structures in the Devonian Rocks near Plymouth, Devon

Published online by Cambridge University Press:  01 May 2009

W. K. Fyson
W. K. Fyson
Affiliation:
Geology Department, University of Ottawa, Ottawa, Canada.
Get access Rights & Permissions [Opens in a new window]

Abstract

Minor folds in slates and sandstones are upright in the south and northerly overturned towards the north, and plunge approximately E.N.E. and W.S.W. towards three major N.W.–S.E. dextral faults. The folds are monoclinal and angular; regardless of attitude, the short limbs lie on the northerly sides of anticlines. Both slaty and fracture cleavages tend to parallel axial planes and local directions of extension. Similarly, the vertical axial planes may closely parallel those of major folds.

Boudins and W.N.W.–E.S.E. dextral oblique faults indicate extension along fold hinges, N.W.–S.E. dextral cross faults a change to N.–S. compression. Folded basic dykes parallel to faults and joints suggest early initiation of the fractures.

Type
Articles
Information
Geological Magazine , Volume 99 , Issue 3 , June 1962 , pp. 208 - 226
Copyright
Copyright © Cambridge University Press 1962

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

REFERENCES

Anderson, E. M., 1951. The Dynamics of Faulting. Edinburgh.Google Scholar
Bott, M. H. P., Day, A. A., and Masson-Smith, D., 1958. The Geological Interpretation of Gravity and Magnetic Surveys in Devon and Cornwall. Phil. Trans., Series A., No. 992, 251, 161–191.Google Scholar
Coe, K., 1959. Boudinage Structure in West Cork, Ireland. Geol. Mag., 96, 191–200.CrossRefGoogle Scholar
Dearman, W. R., 1959. The Structure of the Culm Measures at Meldon, near Okehampton, North Devon. Quart. J. geol. Soc. Lond., 115, 65–106.CrossRefGoogle Scholar
Dearman, W. R., and Butcher, N. E., 1959. The Geology of the Devonian and Carboniferous Rocks of the North-west Border of the Dartmoor Granite, Devonshire. Proc. Geol. Ass., Lond., 70, 51–92.CrossRefGoogle Scholar
Dineley, D. L., 1961. The Devonian System in South Devonshire. Field Studies, 1, 121–140.Google Scholar
Flinn, D., 1952. A tectonic Analysis of the Muness Phyllite Block of Unst and Uyea, Shetland. Geol. Mag., 89, 263–272.CrossRefGoogle Scholar
Hendriks, E. M. L., 1951. Geological Succession and Structures in Western South Devonshire. Trans. R. geol. Soc. Cornwall, 18, (3), 255–308.Google Scholar
Lambert, J. L. M., 1959. Cross-Folding in the Gramscatho Beds at Helford River, Cornwall. Geol. Mag., 96, 489–496.CrossRefGoogle Scholar
Nadai, A., 1959. Theory of Flow and Fracture of Solids. McGraw-Hill, New York.Google Scholar
de Sitter, L. U., 1954. Schistosity and Shear in Micro- and Macrofolds. Geol. en Mijnb., 16, 429–439.Google Scholar
Taylor, P. W., 1950. The Plymouth Limestone. Trans. R. geol. Soc. Cornwall, 18, (2), 146–214.Google Scholar
Tidmarsh, W. C., 1932. The Permian Lavas of Devon. Quart. J. geol. Soc. Lond., 88, 712–775.CrossRefGoogle Scholar
Ussher, W. A. E., 1904. Geology of the Country around Kingsbridge and Salcombe. Mem. geol. Surv. U.K., 355, 356.Google Scholar
Ussher, W. A. E., 1907. The Geology of the Country around Plymouth and Liskeard. Mem. geol. Surv. U.K., 348.Google Scholar
Ussher, W. A. E., 1912. The Geology of the Country around Ivybridge and Modbury. Mem. geol. Surv. U.K., 349.Google Scholar