Excursion to Finchley. May 31st, 1873 - Geologists' Association excursion

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From: A record of excursions made between 1860 and 1890. Edited by Thomas Vincent Holmes , F.G.S. and C. Davies Sherborn, F.G.S. London: Edward Stanford [For the Geologists’ Association], 1891. Source: Cornell University copy on the Internet Archive (Public domain work)

Director: Henry Walker, F.G.S. (Report by The Director. ) (Proc. Vol. iii. p 2-4.)

[Finchley and neighbourhood. The first excursion to this district was made in 1866, and was unrecorded in the Proceedings.]

From East End station the company retraced their route for a short distance, and stood on the lofty railway embankment over the valley traversed by Mutton Brook, in order to survey the geographical features of the Finchley district, in so far as those features have been determined by the Glacial Beds. By the aid of an enlarged copy of part of the Geological Survey Map (Superficial Deposits), the Finchley Glacial District was seen to form a roughly triangular plateau. The base of the triangle runs nearly due east and west—from Muswell Hill nearly to Hendon—whilst the apex is• found near East Barnet. The base and western side of the plateau were seen to be bounded by well-marked valleys, which define the limits of the Glacial beds and tell of the meteoric agencies which have helped to reduce them to their present limits. Descending the embankment the party crossed the valley and entered upon Glacial ground, each member receiving a copy of the enlarged map already described. A halt was made at Marylebone Cemetery, where, at the lodge gates, were seen a number of the characteristic drift fossils of the district, especially gryphæas, belemnites, and ammonites, which are yielded plentifully from the Boulder Clay at this spot. The excursion was then continued past the Manor House moat and pond, across the Edgware and Highgate Railway to the Manor brickfield, Finchley. Here, by the courtesy of Mr. Charles Plowman, the proprietor, some interesting sections were open to inspection. Mr. Walker then proceeded to explain the nature and review the history of the exposed deposit—the Boulder Clay of the southeast of England. The accumulations at this spot belong to the period of the great submergence of England beneath the Glacial sea, and are not the immediate products of land-ice. The relation of the Finchley and Muswell Hill Glacial Beds to the Essex outliers of the same deposits was then exhibited, Mr. Searles V. Wood, jun., having kindly forwarded to Mr. Walker his Drift Map of Essex for this purpose, as well as numerous sections across the valley of the Lea, showing the former connection of the deposits now divided by that valley. At the conclusion of the address a collection of fossils, obtained by Mr. Plowman from the pit in which the company were assembled, was exhibited by that gentleman; after which the members themselves made a successful search, many fossils from the Oxford Clay, Lias, Oolite, and Chalk being discovered, as well as rocks of great variety, including striated chalk pebbles and boulders. The party subsequently proceeded to the higher ground, near Finchley Station, facing Mill Hill, where Mr. Caleb Evans described the physical features of the country, and exhibited sections illustrative of the range and outcrop of the various formations.

[There was an excursion to Whetstone and Finchley on April 23rd, 1887, the Directors being J. G. Goodchild and H. B. Woodward. A report of it may be seen in the Proceedings (vol. x. p. 145). Pinner was visited on June 26th, 1886. For report see Proc., vol. ix. p. 548.]

Map

See Excursion to Hampstead, (p. 144).

Books

W. Whitaker, Geology of London, 2 vols., 8vo, London (Geol. Surv.). 1889. 11s. [For literature.]

J. Morris, Note on the Gravel Beds of Finchley, Geol. Mag., vol. v. 1868, p. 411.

H. Walker, The Glacial Drifts of Muswell Hill and Finchley, 8vo, London. 1874.