Hostname: page-component-78c5997874-8bhkd Total loading time: 0 Render date: 2024-11-17T21:24:24.500Z Has data issue: false hasContentIssue false

Petrology of the Bodmin Moor granite (eastern part), Cornwall

Published online by Cambridge University Press:  14 March 2018

P. K. Ghosh*
Affiliation:
Imperial College of Science and Technology, London

Extract

This paper presents the results of an investigation of the granite composing the eastern part of Bodmin Moor, Cornwall, as mapped on Sheet no. 337 of the Geological Survey. The work was undertaken on the suggestion of Dr. J.W. Evans, and comprised the field- and laboratory-work necessary for a detailed study of the petrology and tectonics of the area.

The boundary of the granite, as mapped by the Geological Survey, has been retained, and also the distribution of the two main granite types ('coarse' and 'fine') shown on the Survey map. The coarse granite, however, has been sub-divided into two varieties, and it has been found practicable to map the distribution of each (fig. 1).

The killas inclusions in this granite have not hitherto been studied, and these have received due attention. Similarly, the minor intrusions described include some that have not been previously recorded.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1927

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

page 288 note 1 Cf. the occurrence on Dartmoor described by DrBrammall, A., Proc. Geol. Assoc, 1926, vol. 37, pp. 262264 Google Scholar.

page 288 note 1 Geol. Survey Sheet Memoir, no. 337 (The geology of the country around Tavistock and Launceston), 1911, p. 70.

page 289 note 1 A. Brammall, loc. cit.

page 292 note 2 Richardson, Cf. W. A., A micrometric study of the St. Austell granite. Quart. Journ. Geol. Soc, 1923, vol. 79, p. 553 Google Scholar.

page 293 note 1 This implies a large content of soda: J. P. Iddings, Rock Minerals, 1911, p. 235.

page 293 note 2 Sederholm, J. J., Bull. Comm. Geol. Finlande, 1916, no. 48, p. 63 Google Scholar.

page 295 note 1 Flett, J. S., Geol. Survey Sheet Memoirs, 335 ; 336, p. 54 Google Scholar.

page 295 note 2 Flett, J. S., Geol. Survey Sheet Memoir, 347, pp. 58, 59.Google Scholar

page 295 note 3 Richardson, W. A., Quart. Journ. Geol. Soc, 1923, vol. 79, p. 565 Google Scholar.

page 296 note 1 Franchi, S., Boll. K. Com. Geol. Italia, 1893, no. 43 Google Scholar.

page 296 note 2 Rosenbusch, H., Mikroskopische Physiographie, 1907, vol. 2, p. 41 Google Scholar.

page 298 note 1 Geol. Survey Sheet Memoir, 347, p. 58.

page 299 note 1 Geol. Survey Sheet Mem. 335, 336, p. 57.

page 300 note 1 Blanck, E. and Rieser, A., Chemie der Erde, 1925, vol. 2 Google Scholar, 15. [Min. Abstr., vol. 3, p. 41.]

page 301 note 1 Bowen, N. L., The behaviour of inclusions in igneous magmas. Journ. Geol., 1922, vol. 30, pp. 513570.CrossRefGoogle Scholar

page 301 note 2 J. W. Evans, Quart. Journ. Geol. Soc, 1921, vol. 77, p. 133 (discussion on Tilley's paper).

page 301 note 3 N. L. Bowen, loc. cit.

page 305 note 1 Tilley, C. E., Quart. Journ. Geol. Soc, 1924, vol. 80, pp. 68, 69.Google Scholar

page 305 note 2 Bowen, N. L., Journ. Washington Acad. Sci., 1925, vol. 15, p. 280 Google Scholar. [Min. Abstr., vol. 3, p. 88.]

page 305 note 3 Tilley, C. E., Paragenesis of the minerals of the three component system MgO-Al2O3-SiO2 in thermal metamorphism. Geol. Mag., 1923, vol. 60, pp. 101107 Google Scholar.