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The Relative Age of Concretions

Published online by Cambridge University Press:  01 May 2009

Extract

The age of a concretion, relative to that of the parent-rock, must be either:—

1. Contemporaneous.—The concretion grew on the sea-floor at the same time, and at about the same rate, as the surrounding deposit was laid down.

2. Penecontemporaneous.—The concretion segregated more or less close to the surface of recently deposited sediment.

3. Subsequent.—The concretion formed after deposition had finished, and after the strata had largely consolidated, but, perhaps, before cementation had taken place to any noteworthy extent.

Type
Original Articles
Copyright
Copyright © Cambridge University Press 1921

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References

page 115 note 1 Dean, , Amer. Journ. Sci., vol. xlv, 1918, p. 411.CrossRefGoogle Scholar

page 115 note 2 Gardner, ibid., vol. xvi, 1908, p. 457.

page 117 note 1 Swinnerton, , Proc. Geol. Assoc., vol. xxix, 1918, p. 20.Google Scholar

page 118 note 1 Raisin, , Proc. Geol. Assoc., vol. xviii, 1903, p. 75.Google Scholar

page 118 note 2 Tarr, , Amer. Journ. Sci., vol. xliv, 1917, p. 428.Google Scholar

page 119 note 1 Murray, , & Hjort, , The Depths of the Ocean, London, 1912, chap.iv.Google Scholar

page 120 note 1 Sorby, , Quart. Journ, Geol. Soc., vol. lxiv, 1908, p. 216.Google Scholar

page 120 note 2 Moisey, , Geol. Mag., 12. V, Vol. V, 1908, p. 222.Google Scholar

page 120 note 3 Liesegang, , Geologische Diffusionen, Dresden and Leipzig, 1913, chap. vi.Google Scholar

page 121 note 1 Geikie, , Structural and Field Geology, Edinburgh, 1912, p. 121.Google Scholar

page 122 note 1 Liesegang, , loc. cit., chap, xviii.Google Scholar

page 123 note 1 Lang, , Proc. Geol. Assoc., vol. xxvi, 1915, p. 117.Google Scholar

page 123 note 2 Davis, , Bull. Dept. Geol. California Univ., vol. LL, vol. II, vol. 11, No. 3, 1918, p. 394.Google Scholar