DRJFIS OF FLAMBOROUGH HKAD. -f U / 



])eriod was oiio of elevation *. This point, however, may bo reserved 

 for further discussion and for the accumuhition of fresh evidence. 



Thin chalky gravel (5) covers the shell-bed ; this, in turn, is over- 

 lain by 10 feet of dark Busenient Clay (4) t ; and this by sand 

 and c:ravel (the Intermediate Series, 3 b) 5 feet, thickening rapidly 

 northward ; while at the top there is about 30 feet of brown or 

 reddish Boulder-clay (3). 



North of this section the cliff is a mass of slips, among which it is 

 just possible to trace the shell-bed down the pre-Glacial denudation- 

 slope of the Secondaries to beach-level under (jrill Cliff, where it may 

 sometimes be seen under the drift when the foot of the cliff is 

 washed bare of shingle. Still farther north I have detected traces 

 of it between tide-marks off Keighton t (one mile) ; and a similar 

 deposit seems to have been passed through in a recent well-boring 

 close to Filey Station, four miles distant. 



(t) File)f Bay, i^c. — The sections north of Speeton lie beyond the 

 limits of my area, but a few notes on them will be requisite lor use 

 in the concluding discussion. 



Between Speeton and Filey the cliffs, from 100 to 150 feet in 

 height, cross the drift-choked entrance to the Vale of Pickering and 

 are composed entirely of Glacial deposits. The arrangement of the 

 beds bears much resemblance to that in Southern Holderness §. 

 Three, or even four, belts of Boulder-clay are sometimes traceable, 

 differing in colour and other respects, and separated by irregular 

 seams of sand and gravel. The lowest of these possesses all the cha- 

 racteristics of the Basement Clay of Flamborough. Xear Mile Haven 

 it includes several huge transported masses of Lower Lias, with the 

 original bedding and fossils still preserved |:, and similar masses of 

 Upper Lias also occur in the vicinity %. The uppermost clay re- 

 sembles in every respect the Upper Clay of Flamborough and of 

 the Holderness sections. Between the upper and lower clays we 

 find in some places Boulder-clay comparable to the Purple Clay of 

 Holderness, while in others only stratified beds of sand or rough, 

 morainic gravel occur, often exhibiting arched bedding. 



These Filey-Bay sections may be taken as types for all the drift- 



* I am sometimes inclined to think that the elevation of the Speeton bed 

 may be a local phenomenon due to the upward bulging of the plastic Lower- 

 Cretaceous clays mider the weight of the Chalk escarpment ; I have not, 

 however, been able to collect any satisfactory evidence for such a movement to 

 anything like the extent indicated. 



t In my former description of the section {supra cit.) I supposed this to be 

 * Lower Purple ' Boulder-clay, not being then aware of the northward extension 

 oi the Basement Clay. 



\ See 'Glacial Beds in Filev Bav,' Proc. Yorks. Geol. & Polvtechn. Soc. 

 vol. vii. (1879) p. 167. 



§ See comparative sections in the above-quoted paper, 



II These masses have sometimes been mistaken for beds in place. See Quart, 

 Journ. Geol. Soc. vol. xlv. (1880) p. o80 (footnote). 



•" Leckenby, 23rd Rep. Scarborough Phil. Soc. (1855) p. 49. I have not yet 

 seen these Upper-Lias masses, which are only oecasionally exposed on the fore- 

 shore, but have recently examined a collection of fossils obtained from them. 

 The Lower-Lias boulders are alwavs visible in the cliff. 



