Excursion to Sandgate and Folkestone. June 19th, 1876 - 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)
Figure 32 Section of the Upper Neocomian Beds, Folkstone.

Director: F. G. Hilton Price, F.G.S. (Report by The Director.) (Proc. Vol. iv. p. 554.)

Note: Folkestone, Sandgate and Hythe. [At the conclusion of the Easter Excursion of 1885 the members of the Association who were present returned to London from Sandwich. Deal, however, remains unvisited, and though Dover was the scene of an excursion on August loth, 1863, no record appears to exist of the sections then seen. But Folkestone seems to have been the very first place ever visited by the Association, the date of this first Excursion having been April 9th, 1860. In Proc., vol. i., p. 47, it is stated that the party "proceeded at once to the shore, and spent several hours in examining the Chalk, Greensand, and Gault, as exhibited in East Wear Bay, the Warren,. and Copt Point, and procured several specimens of the characteristic fossils." The succeeding excursions to Hythe and Folkestone took place in 1864, 1865, and 1866, during the period when no Proceedings were issued; their details consequently remain unrecorded. Excursions to Folkestone and the neighbourhood are, however, chronicled in the Proceedings, one in 1870, another in 1876, and a third in 1883. As the account of the last of these is best adapted to serve as an introduction to this district it is here given first.]

Excursion to Sandgate and Folkestone. June 19th, 1876

Alighting at the Shorncliffe Camp Station the party proceeded along the Sandgate Road towards the shore, passing over the high ground above Sandgate, which is composed of the Folkestone Beds of the Upper Neocomian bed No. 3 of Price's section, (see paper on the " Lower Greensand and Gault of Folkestone," Proc. Geol. Assoc., vol. iv. p. 139.)

Having arrived on the shore the undercliff was examined, where the junction between bed No. 3 and bed No. 2 was plainly seen, showing the calcareous gritty beds reposing on the dark-greenish " hassocky " beds of No. 2 and No. T. Proceeding towards the turnpike on the Lower Sandgate Road, the opportunity was afforded of inspecting the Sandgate Beds of the Upper Neocomian, coming on gradually and just below the turnpike, and of examining the base-bed of the Sandgate series (the Rhynchonella sulcata zone), all of which beds dip N.N.E., therefore as the party walked eastward they gradually came upon higher formations. Many pieces of pyritized wood were collected in bed No. 1 of the Sandgate series. The whole of the upper cliff from Sandgate to Folkestone Harbour is chiefly composed of the Third Division of the Folkestone Beds of the Upper Neocomian, the Gault coming on just above the harbour. The Director pointed out the position of the "Elephant Bed," at the Battery, at the eastern corner of the West Cliff, none of which is now visible, it having been mostly dug out when the Battery was constructed.

After a short explanation of the fine cliff section of the Upper Neocomian series, with the Gault capping it, the members walked down to the shore to examine the Folkestone Beds of the Upper Neocomian, so well shown at this point. Owing to the continued prevalence of westerly winds the greater portion of the Sandgate Beds were buried in sand; only the upper part of bed No. 4 of that series was seen in situ. At low spring tides the whole of the Sandgate Beds may be seen near the harbour, together with the zone of Rhynchonella sulcata (bed No. 1), which receives its name in consequence of the abundance of that shell. The whole of the Folkestone Beds, however, were well examined; these beds gradually dip away towards Copt Point. Many of the members collected a few fossils, and saw many fine specimens of Exogyra and Pseudodiadema, which owing to the hard nature of these beds they were unable to obtain. The Director pointed out the various zones, and showed the position of the Ammonites mammillaris zone in the cliff, the Junction Bed between the Upper Neocomian and the Gault, with the sulphur-band of the zone of Ammonites interruptus resting upon it. As Copt Point is turned, these beds are hidden beneath the sea, and the beds of the Lower and Upper Gault, which form the cliff at this point, become more accessible.

In East Wear Bay the Gault beds are no longer in situ as at Copt Point, for, owing to frequent landslips, they have been thrown down, and form the floor of the sea-shore. It being low water at the time of the visit, the members were able to examine the lithological and palœontological characters of the various zones, which were explained by the Director. John Griffiths, the well-known fossil collector of Folkestone, disclosed with his pickaxe the richness of the formation, and many typical fossils were collected.

Having passed over the Gault, Mr. Price pointed out the junction between the Upper Gault and the so-called Upper Greensand, which rests conformably upon the Gault, with a few pipings of the dark-green marly sand passing down into the marly beds of the Upper Gault. This deposit is only about fourteen feet in thickness here, and passes gradually into the Chalk Marl, the green grains continuing upwards for several feet. The Upper Greensand is poor in organic remains; the Chalk Marl, on the contrary, is very fossiliferous, and is about ten feet in thickness.