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The Base of the Devonian, with special reference to the Welsh Borderland

Published online by Cambridge University Press:  01 May 2009

Extract

In 1916 the writer carried out a field survey of a district in Shropshire in which the “passage beds” between the Silurian and “Old Red Sandstone” are well developed. So apparent was the difficulty of drawing a dividing line between the two systems that a description of the district was published without a decision being reached. Shortly afterwards active service in France and Belgium brought opportunities of studying both field and museum evidence there. The writer came to conclusions which he afterwards found agreed very closely with those reached shortly before by MM. Barrois, Pruvost, and Dubois, who had approached the problem from a different standpoint. A preliminary summary was published, and in 1920 the Council of the Geological Society awarded the author the “Daniel Pidgeon Fund” for the purpose of enabling him to carry out a comparative study of the Downtonian and Gedinnian. The results were laid before the Society in November, 1921. The Council have, however, declined to publish the paper, though their decision in this matter was not communicated to the author until nine months after the reading of the paper. A short summary of the results obtained (but not of the field evidence) has been published in Belgium. The main object of the present note is to place on record the field-work on which the general conclusions are based. One of the principal objections to the writer's conclusions which was raised when the paper was read before the Geological Society was that “the question where the line between the Silurian and the Devonian was to be drawn should be primarily determined in areas in which normal marine conditions had prevailed, not in one of exceptional character, like the Welsh Borderland”.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1923

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References

page 276 note 1 Stamp, , “The Highest Silurian Rocks of the Clun Forest District, Shropshire”: Quart. Journ. Geol. Soc., vol. lxxiv, 1918, pp. 221–44.CrossRefGoogle Scholar

page 276 note 2 Barrois, , Pruvost, , & Dubois, , “Sur les couches de passage du Silurien au Dévonien dans le Bassin houiller du Pas-de-Calais”: C.R. Acad. Sci., vol. clxvii, 1918, p. 705.Google Scholar

page 276 note 3 Stamp, , “Note on the Determination of the Limit between the Silurian and Devonian Systems”: Geol. Mag., Vol. LVII, 1920, p. 57.Google Scholar

page 276 note 4 Stamp, , “The Base of the Devonian, with especial reference to the Welsh Borderland”: Abs. Proc. Geol. Soc., No. 1075, November 19th, 1921, p. 6.Google Scholar

page 277 note 1 Stamp, , “La base du système dévonien en Angleterre”: Bull. Soc. belge Géol, vol. xxxi. 1921, pp. 8798.Google Scholar

page 277 note 2 Abs. Proc. Geol. Soc., No. 1075, 19th November, 1921, p. 8.Google Scholar

page 277 note 3 Barrois, , Pruvost, , & Dubois, , “Description de la Faune siluro-dévonienne de Liévin”: Mém. Soc. Géol. Nord., vol. vi (II), pt. ii, 1920 (1922); see review in Geol. Mag., Vol. LX, 1923, p. 92.Google Scholar

page 277 note 4 Jones, , “The Valentian Series”: Q.J.G.S., vol. lxxvii, 1921, p. 144.CrossRefGoogle Scholar

page 277 note 5 Elles, , “The Zonal Classification of the Wenlock Shales of the Welsh Borderland”:Google Scholar Ibid., vol. lvi, 1900, p. 370.

page 278 note 1 Elles, & Slater, , “The Highest Silurian Rocks of the Ludlow District”:Google Scholar Ibid., vol. lxii, 1906, p. 195.

page 278 note 2 Wood, , “The Lower Ludlow Shales of the Welsh Borderland”:Google Scholar Ibid., vol. lvi, 1900, p. 415.

page 278 note 3 Stamp, , “The Highest Silurian Rocks of the Clun Forest District”:Google Scholar Ibid., vol. lxxiv, 1918, p. 221.

page 278 note 4 Peach, & Horne, , “The Silurian Rocks of Britain: Vol. I, Scotland”: Mem. Geol. Surv., 1899.Google Scholar

page 278 note 5 Stamp, , op. cit., 1920.Google Scholar

page 279 note 1 London and Edinburgh Philosophical Magazine, N.S., vol. vii, pp. 4552.Google Scholar

page 279 note 2 Silurian System, 1839, p. 7.Google Scholar

page 279 note 3 Proc. Geol. Soc., vol. ii, pp. 913 (8th January, 1834).Google Scholar

page 279 note 4 Op. jam. cit., 1834.Google Scholar

page 279 note 5 Siluria, 4th edition, 1867, p. 133.Google Scholar

page 279 note 6 Ibid., p. 134.

page 281 note 1 Professor Hull attempted to overcome the difficulty by the creation of a “Siluro-Devonian System” to include the passage-beds above the Ludlow Bone-bed. Q.J.G.S., vol. xxxviii, 1882, p. 200.Google Scholar

page 281 note 2 Leriche, , “Observations sur la limite entre le Silurien et le Dévonien … à propos d'une note de M. Stamp”: Bull. Soc. belge Géol., vol. xxxi, 1921, pp. 158–66.Google Scholar

page 281 note 3 de Dorlodot, , “Le Système dévonien et sa limite inférieure”: Ann. Soc. géol. Belg., vol. xxxix, 1912, Mém., pp. M 291M 371; also Conclusions …,Google Scholar Ibid., Bull., pp. B 242–5.

page 281 note 4 Williams, , Bull. Geol. Soc. Amer., vol xi, 1900, pp. 334–5.Google Scholar

page 281 note 5 Op. cit., 1920 (1922), pp. 205–16.Google Scholar