"V"©!, 68.] GLACIATiON OF THE BLACK COMBE DISTRICT. 430 



Hycemoor is sandy, and the railway-cnttings south of Bootle, as 

 also near Millom, show the presence of a great amount of sand 

 and gravel with smaller interstratified heds of clay. Some 9 feet of 

 stratified gravel has been exposed at Bootle Union Workhouse ; 

 and a section about 350 yards west of Par End also showed 

 layers of red sand beneath gravel. Other sections occur near 

 Kirksanton. 



These deposits rest upon the Lower Boulder Clay, which rises 

 from beneath them and climbs the rising flanks of Black Combe, or 

 occupies the lower ground (as, for example, seaward of Silecroft 

 and Millom) where the sands are absent (see fig. 2, p. 415). 



Since, therefore, an almost continuous sequence of events has 

 been traced from the time of maximum glaciation to the formation 

 of the marginal channels, when the ice-front stood close to the hills, 

 it is evident that the sands and gravels of the plain must have 

 been formed at a later date. 



The general level of the plain is rarely higher than 100 feet, 

 although, at The Hawes, near Annaside Bank, it rises to 159 feet. 

 It has been considerably dissected by post-Glacial denudation, 

 which has had the effect of accentuating the original diversities of 

 its surface.^ Here and there small sheets of water, such as Barfield 

 Tarn, a mile south of Bootle, lie in the hollow depressions (probably 

 old kettle-holes). 



Between Eskmeals and the Annas, south-west of Bootle and 

 east of the railway, there is a long low-lying valley suggestive 

 of an old marginal channel, now drained by streams flowing in 

 both directions from a low watershed near Bootle Workhouse. 

 In this neighbourhood are several other hollows and ridges, 

 running north and south, which appear to be original features, 

 slightly accentuated by denudation. 



Taking everything into consideration, I am of opinion that 

 the sands and gravels of the plain were accumulated during the 

 period which foUoAved upon the cutting of the lowest undoubted 

 marginal channels, and that the water from the melting ice, 

 fortified by that from Eskdale, etc., was more frequently spread 

 out over a large area than concentrated in definite channels, because 

 of the relatively low surface-gradient. 



In the main, the material was deposited beyond the ice-limit, 

 frequently in stratified layers beneath temporary sheets of water; 

 but other parts were formed in a more irregular and tumultuous 

 manner by torrential action. The deep hollows or kettle-holes 

 are probably due to blocks of gravel-covered ice which, becoming 

 detached from the ice-sheet, melted out and allowed their covering 

 of drift to sink into the hollows thus formed. 



A comparison may be made with the gravels of the northern 

 side of Nunatak Eiord, Alaska, which form a series of benches 

 altogether about a mile in width, the Eiord itself being only from 



^ Which would have been first toned down by the deposit of Upper Boulder- 



Clriy. 



Q. J. G. S. No. 271, 2 1 



