Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/312

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204 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Jan. 12,


and sand, capping the higher ground at Rugby and Clifton, and descending into the valley, where they increase in thickness ; c, c, the supposed position of the Lower Lias clay on which the drift lies.

In a section taken across the valley of the Avon, from the summit of the hill on which the town of Rugby stands to the Brownsover intrenchments, excavations made on different parts of the hill show that the Boulder-clay, with its associated beds of gravel and sand probably extends some distance down its flanks. A boring made on the line of section near the river came upon the Lias at a depth of six feet from the surface. On the hill towards Brownsover the existence of the Boulder-clay and other drift could only be inferred. The modern alluvium on each side of the river is the only freshwater deposit apparently existing thereabouts.

Fig. 2 represents a typical section across the Avon valley, from the summit of Bredon Hill to the top of Cracombe Hill, which is taken along such parts of the valley as illustrate in the best manner the relative distribution of the different classes of the superficial deposits.

Provisional Classification of the superficial Deposits of the Valley of the Avon and adjoining districts*.

Upper Series, ranging from 430 feet to 300 feet above the sea:-

  • The letters refer to the localities

in the Table (p. 216) ; and the numbers denote the order of the succession of the beds from the surface of the ground downwards.