Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/398

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portant addition to the geology of the neighbourhood, the mapping of the London Clay here *, the only part of France, I believe, where it has been found.

In the following description the same numbers have been used for the same beds in the two sections noted, as far as could be.

Westward from Dieppe, along the top of the cliff, there are great hollows and pipes of Tertiary sand and drift, with many slips, the clearest giving the section below : —

1. Gravel, of subangular flints and flint-pebbles.

3. Oldhaven Beds ? Fine light-brown, buff, or light-grey sand.

4. Laminated brown clay.

5. Shelly clay, with a thin layer of shelly stone, over 2 feet. (Light grey (whitish) sharp sand, with ferruginous layers, about a foot.

6. Grey and brown clayey sand, with peaty layers, especially at bottom, about a foot.

8. Sharp rather coarse sand, whitish just at top, the rest pale greenish and yellowish grey, with iron-stains near the bottom. Some small green-coated flints, and at the bottom a layer of them (9), 6 or 7 feet, resting evenly on

10. Chalk with flints, but not with such marked layers of them as occur a little below.

Further westward the ground falls to the valley of the small river Scie. Beyond the next gap, which is small, there is at the highest part a great hollow, of drift loam, flints, and pebbles, and of the Tertiary beds. All have fallen much, right down to the beach ; but at the top at one spot I saw above the fine sand (3) a mass of clay, the lowermost part brown and sandy, the rest of a dark greenish grey, like the bottom London Clay of East Kent. There may be a fault here, as the Tertiary beds seem to abut against the Chalk.

At the top of the cliff beyond the next gap, also small, there was at the time of my visit a very good section reaching for a long way, and showing the following beds.: —

1. Flint-gravel.

(Evenly bedded alternations of dark-grey and brown shaly clay, brown sand (some like that of the Oldhaven Beds), and loam, 12 or 15 feet.

Brown clayey sand with thin layers of clay, drying hard, 5 or 6 feet?

3. Oldhaven Beds. Fine light-coloured evenly bedded sand, at one place with a bed of iron- sandstone more than a foot thick. Over 25 feet. (The beds below much slipped and not easily to be seen, so that some may have escaped notice, for instance No. 4. of the former section.)

5. Shelly clays, much thicker than before, evenly bedded, divided into two by a dark-grey and greenish clay. A little dark clay with layers of sand. 6. Lignite and peaty clay. A little grey and ferruginous clay. 8. Sharp buff sand, with concretionary masses of greywether- sandstone (as noticed by Mr. Prestwich) and a few flints. 9. Flints in what seems to be a greenish clay (inaccessible) filling small pipes in 10. Chalk. *

  • The Greenough Geol. Map of England, south-eastern sheet, 1865.