STJCCESSIOJf IN THE TRENT BASIN. 453^ 



the Wreak valley, where it rests upon the Quartzose Sand, the only- 

 exposure to be seen is in the brick-yard at Eotherby. Here it form& 

 the upper portion of the ridge which extends in the direction of 

 Kirby Bellars. It is a silty tough clay full of boulders ranging in 

 age from Lias to Carboniferous. 



I am indebted to Mr. J. J. Harris Teall and to Mr. J. Shipman for 

 a description of the sections which were exposed in the railway- 

 cuttings between Melton Mowbray and Nottingham. Though there 

 is no absolute certainty that the whole of the deposits occurring 

 beneath the Chalky clay, now to be described, belong to this stage, 

 yet, in the absence of direct proof to the contrary, I shall consider 

 them here. 



In the cutting at the mouth of the Stanton-Hill tunnel the Tea- 

 green Marls are covered by black Rhaetic shales which have been 

 thrown into zigzags, gradually diminishing in acuteness as the eye 

 follows them down to the bottom of the section. These crumplings 

 could be seen on both sides of the line, and it was clear from their 

 trend that the ice-sheet which produced them must have come from 

 the north-west. The Paper Shales are largely mixed up and 

 redeposited with a brown sandy Boulder-clay which rests above. 

 To be more accurate, this drift consists of a matrix of stiff bluish 

 or purplish-brown Boulder-clay, evidently very largely derived from 

 the grinding down of Lias, and Ehsetic and Keuper marl. It was 

 full of lumps and fragments of the same rocks, Lias being most 

 plentiful, along with pebbles of quartz, pieces of fibrous gypsum 

 from the Upper Keuper, boulders of Millstone Grit, encrinital lime- 

 stone, and Coal-measure sandstone, all mixed together in the most 

 confused manner. Many of the rock-fragments were smoothed and 

 poHshed, and some distinctly striated. One of the boulders, a mass 

 of Millstone Grit, stood three feet in height, and was more than 

 eleven feet in circumference. The drift shows little or no signs of 

 stratification, and has evidently been subjected to immense lateral 

 pressure from a north-westerly direction. Resting upon this Boulder- 

 clay, and probably, like the mass in the Aylestone section, torn up 

 from the Quartzose Sand, come about 14 feet of loose reddish-brown 

 sand with pebbles and occasional false-bedding. The whole mass 

 showed signs of having undergone considerable lateral pressure, and 

 the contortions could be clearly traced in the deposit of sand by the 

 tortuous bedding of the strings of pebbles in it. These two deposits, 

 the brown Boulder-clay and sand, were confined to the north end of 

 the tunnel, and contained no traces of recent shells. 



In the Plumtreo cutting there is similar sandy Boulder-clay, but 

 it had been greatly disturbed by the Chalky Clay, a small thickness 

 of which capped it. 



III. Middle Pleistocene Epoch. 



1. Melton Sand, 



2. Great Chalhy Boulder-clay. 



3. Chcdky Gravel. 



The deposits formed in the Trent basin during the Middle Pleis- 

 Q.J.G-.S. No. 168. 2 I 



