462 ME. E. M. DEELEY ON THE PLEISTOCENE 



20 feet of strong clay with concretions and beds of sand. The clay 

 is laminated and, like the sand, is free from boulders. The whole 

 deposit is much disturbed, the sand-beds sometimes standing in a 

 vertical position. jS'ear Market-Bosworth station, in another exca- 

 vation, the sandy clay becomes stony towards the bottom. Pebbles 

 of quartz, flint, sandstone, coal, and shale were seen. 



3. Chalky Gravel, 



Eesting upon the Great Chalky Boulder-clay or older rocks, and 

 spreading in great sheets or banks along almost the entire length 

 of the Trent watershed or intervening high lands, there are thick 

 deposits of stratified, flinty, or chalky gravel or sand. Unlike the 

 older Quartzose Sand, the current-bedding in these deposits as 

 frequently slopes to the east as to the west. Along the western 

 portion of the watershed and in areas where the Chalky Clay is 

 absent, the gravel loses its intensely chalky character and rests 

 directly upon the older rocks, the Great Chalky Boulder-clay having 

 apparently entirely thinned out in this direction. To what extent 

 the Chalky Gravel may, in part, be equivalent to the Melton Sand 

 in these westerly sections I cannot say. 



It will be most convenient first to follow the Chalky Gravel in a 

 westerly direction from Lincolnshire and Leicestershire, across that 

 portion of the Trent basin which lies to the south of the river, and 

 then through Nottinghamshire and Derbyshire into Staffordshire. 

 By so doing, the Chalky Gravel will first be seen, with few exceptions, 

 in its intensely chalky condition resting upon or in the immediate 

 vicinity of Chalky Boulder-clay. In the northern and western 

 division it usually overlies older rocks and contains little or no 

 chalk, but numerous flints. 



The occurrence of the Chalky Gravel not only upon the Chalky 

 Clay where it is thickest, but also upon the flanks of the hills, or 

 even resting upon the older rocks at low elevations in the wider 

 vaUeys, proves that though the Chalky Clay has been denuded 

 from considerable areas, it was by no means deposited as a uniform 

 layer over the whole district. Indeed some portions of the main 

 valleys have always been quite free from it. 



On the high lands of Lincolnshire and Leicestershire the Chalky 

 Gravel was evidently deposited in the sea and exposed to the action 

 of currents and icebergs, or even to the temporary readvance of the 

 glacier which formed the Chalky Boulder-clay. 



The oflicers of the Geological Survey * regard some gravel which 

 occurs south and south-west of Coddington, near Newark, as of 

 interglacial age. I have not been able to find any good sections 

 exposing the deposit; but from what could be seen in old|workings, 

 I am inclined to regard this view as correct, and relegate it to this 

 stage. 



Two miles south of Grantham clean, current-bedded, Chalky sand 



* Memoir on the Geology of the south-west part of Lincolnshire. 



