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Metamorphic Rocks of the Sea Floor between Start Point and Dodman Point, S.W. England

Published online by Cambridge University Press:  11 May 2009

F. C. Phillips
F. C. Phillips
Affiliation:
Department of Geology, Bristol University
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Extract

As part of the programme of study of the geology of the western approaches initiated at Bristol by Prof. W. F. Whittard (Whittard, 1962) information has been accumulated concerning the distribution and nature of the metamorphic rocks exposed in a series of inliers between Start Point in the east and Dodman Point in the west.

Early dredgings in this area were described by Worth (1908). Six core samples and two dredgings of metamorphic rocks are listed by Hill & King (1953). Mica schist in situ is recorded by Holme (1953). Various cruises in R.V. ‘Sarsia’ from 1957 onwards have yielded seventeen cores and further dredged samples. Additional material, collected from the exposed parts of the Eddystone reefs or obtained by diving at critical localities, has become available through the kindness of members of the staff of the Marine Biological Laboratory at Plymouth.

Sixteen cores and eight dredged samples serve to demarcate an area of schistose rocks, extending some 24 miles from east to west and 7 miles in maximum width from north to south, off the southernmost part of Devon (Fig. 1). These rocks, with an exception to be noted, compare closely with those exposed on land, between Bolt Tail and Start Point, south of a well defined east-west boundary (Ussher, 1904; Tilley, 1923). There are examples of quartz-muscovite-chlorite schists precisely like the Start Mica-schists and Bolt Mica-schists described by Tilley. Albite porphyroblasts, in a rock dredged near East Rutts (Fig. I, 1262) which is transitional to Tilley's ‘schists of composite origin’, show well the contorted swarms of carbonaceous inclusions which he describes (1923, p. 180).

Type
Research Article
Information
Journal of the Marine Biological Association of the United Kingdom , Volume 44 , Issue 3 , October 1964 , pp. 655 - 663
Copyright
Copyright © Marine Biological Association of the United Kingdom 1964

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References

Curry, D., Hersey, J. B., Martini, E. & Whittard, W. F., 1964. The geology of the Western Approaches of the English Channel. II. Geological interpretation aided by boomer and sparker records. Phil. Trans. B (in the press).Google Scholar
Curry, D., Martini, E., Smith, A. J. & Whittard, W. F., 1962. The geology of the Western Approaches of the English Channel. I. Chalky rocks from the upper reaches of the continental slope. Phil. Trans. B, Vol. 245, pp. 267–90.Google Scholar
Dearman, W. R., 1964. Wrench-faulting in Cornwall and South Devon. Proc. Geol. Ass., Lond., Vol. 74, pp. 265–84.CrossRefGoogle Scholar
Donovan, D. T. & Stride, A. H., 1961. An acoustic survey of the sea floor south of Dorset and its geological interpretation. Phil. Trans. B, Vol. 244, pp. 299–330.Google Scholar
De La Beche, H. T., 1839. Report on the Geology of Cornwall, Devon, and West Somerset. London.Google Scholar
Harker, A., 1950. Metamorphism. London.Google Scholar
Hill, M. N. & King, W. B. R., 1953. Seismic prospecting in the English Channel and its geological interpretation. Quart. J. geol. Soc. Lond., Vol. 109, pp. 1–18.CrossRefGoogle Scholar
Holme, N. A., 1953. The biomass of the bottom fauna in the English Channel off Plymouth. J. mar. biol. Ass. U.K., Vol. 32, pp. 1–49.CrossRefGoogle Scholar
Phillips, F. C., 1961. Structural petrology of the schists of the Start Point area. Abstr. Proc. 4th Conf. Geol. Geomorph. S.W. Engld, R. geol. Soc. Cornwall, pp. 7–8.Google Scholar
Rawson, D. S. & Bell, J. D., 1963. Geology of the East Rutts (South Devon). Nature, Lond., Vol. 200, pp. 770–1.CrossRefGoogle Scholar
Reid, C., 1907. The geology of the country around Mevagissey. (Explanation of sheet 353.) Mem. geol. Surv. Engld & Wales.Google Scholar
Tilley, C. E., 1923. The petrology of the metamorphosed rocks of the Start area (South Devon). Quart. J. geol. Soc. Lond., Vol. 79, pp. 172–204.CrossRefGoogle Scholar
Ussher, W. A. E., 1904. The geology of the country around Kingsbridge and Salcombe. (Explanation of sheets 355 and 356.) Mem. geol. Surv. Engld & Wales.Google Scholar
Whittard, W. F., 1962. Geology of the Western Approaches of the English Channel: a progress report. Proc. roy. Soc. A, Vol. 265, pp. 395–406.Google Scholar
Worth, R. H., 1908. The dredgings of the Marine Biological Association (1895–1906) as a contribution to the knowledge of the geology of the English Channel. J. mar. biol. Ass. U.K., Vol. 8, pp. 118–88.CrossRefGoogle Scholar