Page:Quarterly Journal of the Geological Society of London, vol. 29.djvu/116

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72 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Dec. 18,


and found the sections more clearly exposed than on my previous visit. Owing probably to the unusual rainfall of the autumn, and the consequent washing-down or slipping of the softer sands and clays, the harder bands towards the base of the section were unusually well defined. By standing at a little distance, so as to obtain a clear general view of the cliff-section, I now saw that I had hitherto much underrated the thickness of the lower clays. It was now evident that the strata between the so-called "marine band" and the "variegated beds" of the Wealden must amount to a thickness of nearly one hundred feet, or more than twice the thickness I had previously ventured to assign to them.

The sketch, fig. 1 (which gives a fair representation of the lower

Fig. 1. — Sketch of lower part of Cliff-section at Punfield Cove.


B. Laminated sand and clay, with lignite.

C. Marine band, with Vicarya.

D. Lobster-clay.

E. Sandstone and shell-bed, with Lower Greensand fossils.

F. Atherfield-clay.

G. Grit-bed.

H. Shales of Upper Wealden.

J. Variegated beds of Middle Wealden.

part of the Punfield Section), indicates very clearly the positions of the various groups of strata to which I have now to refer.

In this section the strata J represent the so-called variegated beds of the Middle Wealden.

The strata H, the greater portion of which is covered by vegetation, consist, where visible, of finely laminated sands and sandy clays. These last resemble very much in appearance the "paper- shales" of the Wealden of Compton Bay and Atherfield, but, so far as I had time to observe them, contain only a few minute fish- bones.

The next stratum exposed, marked G on section (fig. 1), is the grit-bed described in my previous paper as probably representing the passage-bed between the Wealden and Neocomian. It consists of a layer of hard sandstone or ironstone-grit, passing downwards, within the thickness of a few inches, into limestone, laminated claystone, and paper-shale. The gritstone contains fish-bones and traces of Cypris. The limestone is here and there crowded with Cypris in the