DAKYNS : GLACIAL BEDS AT BRIDLINGTON. 
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GLACIAL BEDS AT BRIDLINGTON. BY J. R. DAKYNS, M.A., OF 
H.M. GEOLOGICAL SURVEY. 
The chief deposit of Holderness, as is well known, is a great 
mass of Boulder Clay or Till, with interbeds of sand, 
gravel, etc. 
At Bridlington Quay this Boulder Clay is immediately 
overlaid by a set of beds, consisting of sand, gravel, and 
warp. What is the precise relation of this set of beds to the 
glacial deposits as a whole ? 
Immediately north of the town, for the distance of about 
half-a-mile, the cliff is low, being perhaps thirty feet above 
mean tide level. Along this portion of the cliff, the gravels 
immediately overlying the boulder clay are crushed and 
contorted in the strangest fashion, and contain included 
masses of boulder clay, and tongues of boulder clay intruded 
into their midst, as shown in the diagram. The surface of 
the boulder clay is very irregular after a fashion that cannot 
be due to mere aqueous erosion. Wherever there is a 
vertical wall of boulder clay the gravel beds are vertical too, 
the pebbles having their longer axes vertical; and where 
there is an intruded tongue of boulder clay, the beds of 
gravel are bent round conformably to the shape of the 
intruded mass, while at other times all traces of bedding is 
lost in the general smash. 
It is obvious that, after the deposition of the gravels in 
regular layers, or perhaps in some cases during their deposi- 
tion, some force, doubtless that caused by moving masses of 
ice, has crushed the till and gravels together. 
These gravels, then, are clearly of glacial age, though 
posterior to the great mass of boulder clay. 
It is as well, before going further, to note the fact that the 
gravels above described consist to a large extent of chalk 
pebbles. 
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