Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/315

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1870.] LLOYD AVON AND SEVERN VALLEYS. 207


in the Bunter-conglomerate beds in the neighbourhood of Bromsgrove, present in many cases the same appearances ; and some of them are found with cracks across them, which yield to the pressure of the hand.

C (3) has only been observed hitherto at Snitterfield, "VVelcombe Hill, and in a brickfield near the New Inn, Ridgway, accompanying the beds B (2) and F. It varies from about 7 feet to 4 feet in thickness.

D (4). This bed appears to be the one which is most persistent in its occurrence of any in the upper series. It has been traced from the neighbourhood of Rugby, where it attains to a minimum thickness of about 50 feet near Hillmorton, to near Princethorpe, where it occurs both under the Boulder-clay and between it. It is met with again in the neighbourhood of Warwick and Leamington, continuing down as far as the Benches, beyond which there is no certain evidence of its occurrence, although it probably underlies the red loam on Cracombe and Charlton hills. The exact thickness of the bed has not yet been ascertained where it occurs in the neighbourhood of Rugby ; but in the district of the New Red marl it averages about 10 feet in thickness. In some of the localities it contains quartzose pebbles and flints.

E (5). This deposit bears much resemblance to the freshwater gravel hereafter to be described. It appears to be a well-washed bed of gravel and sand, containing pebbles of white quartz, a few flints, and numerous water-worn specimens of Gryphoea incurva and Belemnites. I also obtained from it a fragment of coral and what appeared to be a fragment of Encrinite limestone. It is doubtful whether it exhibits any signs of stratification or not. The only localities in which I have met with it are at Snitterfield, near Warwick, near the Brickyard, Leamington, and Welcombe Hill, near Stratford- on-Avon. It is said to occur near the " New Inn " on the Ridgway.

In order to make clearer the order of superposition of the deposits above described, I subjoin two typical sections — the one taken from the beds occurring in the Lias district, and the other from the area of the New Red marls.

Section A.

ft.

A. (1). Average thickness 7 B. (2). On the high ground 9

   "   When occurring in a valley ... 30 and upwards. 

D. (4). Total thickness unknown ... 50 and upwards.

Basement rock — Lower Lias clay and limestone.

Section B.

ft.

B (2) and F. Average thickness about 10

C. (3) Average thickness about 3

D. (4) Average thickness about 10

E. (5) Average thickness uncertain.

Basement rock principally New Red marl *.

  • Some of the localities, although occurring on the Lias, are in the vicinity

of the New Red marls.