Excursion to the Isle of Sheppey. June 7th, 1875 - 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)

[Sheppey was first visited by the Association in 1861. (Proc., vol. i. p. 166.) The next excursion there took place in 1868, while the publication of Proceedings was suspended. The third excursion, on June 7th, 1875, is reported at some length (Proc., vol. iv. p. 320.) A fourth visit was made on May 23rd, 1881, and a short account of it appears in Proc., vol. vii. p. 149. Sheppey was also the scene of another excursion in 1887, a record of which appears in the excursion, or November, number for that year. The following account is derived from the reports of the visits in 1875 and 1881.]

Excursion to the Isle of Sheppey. June 7th, 1875

Directors: W. Carruthers, F.R.S.; Major F. Duncan, R.A., and W. H. Shrubsole, F.G.S. (Proc. Vol. iv. p 320.)

On arriving at Queensborough, the members were met by Major Duncan and Mr. Shrubsole. Carriages were taken in the direction of Warden Point, at the extreme eastern end of Sheppey. The lower road, through Eastchurch, was chosen, and after a pleasant drive over a country at first somewhat unattractive and bare, but afterwards pretty and well timbered, with fertile vales and swelling elevations, affording glimpses of the sea to the north, the vehicles arrived at Warden Court, where, through the kindness of Mr. C. Payne, Major Duncan was enabled to give his guests a hospitable welcome.

A large collection of the fossils so abundant in Sheppey, pyritized palm-fruits (Nipadites), stems, chelonian and fish remains, together with coprolites and crystals of selenite, exhibited by Messrs. Boughey, Hall, and Atkins, of Sheppey, invited the attention of the party before the road was taken to the cliffs. On the brink of the cliff stand the ruins of a little church, that, not very long ago, was considered to*Occupy a secure position, but which now, so rapid is the destruction of the land by the sea, and so near is the church to the edge of the cliff, it cannot be long before the whole structure is destroyed. [See next report.] Close to the ruins, and with a commanding view of the crumbling masses of London Clay forming the seaward face of Sheppey, the visitors assembled to listen to the President's account of the Flora of the London Clay of Sheppey. (See Proc., vol. iv. p. 318.)

Following Mr. Carruthers, Mr. W. H. Shrubsole, who has been resident in the island for twenty years, informed the visitors that the stems, as well as the fruits of plants, were often found. Landslips here were frequent, and were sometimes extensive, as much as five acres of land having given way at one time. There was a terrace, or lower cliff, which formed, as it were, a buttress to the upper, and, while this endured, the upper cliff remained; but when this support was destroyed by the waves, the upper cliff gave way, and so another undercliff was formed. The rapidity of the destruction of the cliffs is such, that no less than 500 tons of iron-pyrites, derived from the clay washed away by the sea, had been shipped in three months. Septaria are also numerous, and these calcareous masses being washed out like the pyrites, were collected on the beach, and used for the manufacture of cement.

A path along the edge of the cliff led to the course of a stream, by means of which the shore was gained, and the members were enabled to examine the rugged face of the clay, which was well searched for fossil fruits. These, however, did not present themselves in great numbers, but specimens of pyrites, frequently encrusting portions of sterns, were very common. Some chelonian remains were also found.

The London Clay of Sheppey has been estimated by Prestwich to have a maximum thickness of about 480 feet, and is similar in lithological character to the formation in the London Basin generally. Its dissimilarity palaeontologically is, however, very remarkable. The extraordinary number of plant remains which it contains has been dilated upon by Carruthers, and affords ground for concluding that near here a river emptied itself into the London Clay sea. This evidence of the proximity of land is in accordance with the fact that in the Sheppey area remains of turtles[1] are found in abundance, while they are wanting in the London Clay of Middlesex and of Surrey.

Again following the path on the top of the cliff, the site of a Roman pottery-kiln was reached. Mr. George Dowker considered it to have been a "smoulder-kiln," in which clay vessels were placed with charcoal, and the fire sustained by a current of air passing through a channel dug in the earth. At Hensbrook a second descent to the shore was made, and the face of the cliff was then observed for a long distance to the west. Mr. Carruthers described and explained the plants met with, one of which, the Orchis mascula, was in full flower, growing luxuriantly in a sheltered spot, and so afforded an illustration of the peculiarity of its reproductive organs.

Sheppey is mainly, though not altogether, composed of London Clay, for, in a few places, as at Minster, East Church, and at East End, a capping of sands has been observed, and these sands have been mapped by the Survey as the Lower Bagshot Sands, which, in other localities, overlie the London Clay. Perhaps the best exposure of these arenaceous beds in the island is the cliff-section near the end of East-End Lane, where they are seen overlying the London Clay, and have a thickness of about twenty-five feet.

Footnotes

  1. Woodward and Sherborn, Catul. Brit. Fuss. Vert., 1890.