Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/317

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1870.] LLOYD — AVON AND SEVERN VALLEYS. 209


the escarpment the outer edges of the freshwater beds are seen to rest. On the north-west side of the Avon isolated patches of the same class of deposits are found on the upper side of the valley of the Arrow, near Donnington, on the summits of Green Hill, Evesham, Mount Pleasant, Pershore, and on the commons of Shuthanger and Shoebarrow, near Tewkesbury. They may be said to consist, for the most part, of red loam and sand, containing pebbles of white quartz, quartzite, and felstone, associated with a considerable percentage of black flints, which seem, in many cases, but slightly water-worn, besides numerous angular flake-like fragments of a whitish siliceous substance, which appear to be composed either of flint or chert. At Bengeworth Hill and Green Hill, near Evesham, the beds average 5 feet in thickness ; at the former locality the surface of Blue Lias clay on which they rest is much eroded ; their maximum thickness, wherever I have had an opportunity of measuring them, was about 15 feet.

At Berry's Coppice, near Donnington, and on Cropthorne Heath, an unstratified bed of ferruginous gravel contains, in its upper part, small pockets and accretions of a light-coloured siliceous sand, mixed with pebbles (fig. 4). In one part of the pit on Cropthorne Heath I observed a pocket of ferruginous gravel without any intermixture of the whitish sand, in which the pebbles were arranged principally with their longer axes variously inclined, accommodating themselves, as it were, to the truncated conical form of the pocket. In the section a singular ridge and furrow-like outline of the stratified

Fig. 4.— South Face of Gravel-pit on Cropthorne Heath.

a. Light grey vegetable soil with a few pebbles. b. Fine gravel. c. Red sand. d. Fine gravel, e. Red and white sand. f. Coarse ferruginous gravel and loamy sand. g. Blue Lias clay.

portion of the beds is seen, the red sand of which is of a lighter colour than that of the bed below. The pebbles appear to be alike in character throughout the deposit. At Berry's Coppice the highly inclined position of the pebbles in the ferruginous gravel is seen extending throughout a considerable portion of the section. In the same locality stratified sand and gravel was seen near the bottom of the pit. In the seams composed partly of whitish and partly of red