WEYBOURN CRAG, 
139 
seems to be that the two deposits are synchronous^ and that the 
Chillesford Clay passes laterally into the Weybourn Crag, or at 
any rate that the Weybourn Crag is equivalent to the upper part 
of the Chillesford Clay. 
Between Trimingham and Cromer, when the foreshore below 
half-tide is laid bare, there may often be seen greenish laminated 
clay and clay ironstone, with thin seams of sand and lines of 
marine shells, principally in the state of ironstone-easts. The 
clay is often carbonaceous, and eontains a little lignite; mam¬ 
malian bones also occur now and then. The base of the deposit 
has not been reached, for the Chalk seen at Trimingham is 
brought above the sea-level by a glacial disturbance, and no trace 
of the Crag is seen resting on it. It is probable, however, 
that in this area the Chalk does not lie many feet below the 
sea-level. 
The furthest point to the east to which the undisturbed Chalk 
has been traced is about half a mile east of Cromer Jetty, where 
at extremely low tides it is occasionally visible. Owing to th.e 
accumulation of beach the immediately overlying beds have not 
yet been examined, but higher up on the foreshore there are 
laminated clays and ironstone with casts of the ordinary Wey¬ 
bourn Crag shells. These rise to the level of mean tide—giving 
a total thickness of about 10 feet to the Crag. 
The Weybourn Crag has been traced continuously from 
Cromer to Weybourn, except for short distances, where it is cut 
out by channels of the estuarine Forest-bed, or has been ploughed 
out by glacial action, so that Boulder Clay rests immediately upon 
the Chalk. All the sections are so fully described in the Memoir 
relating to this neighbourhood,'^ that it will only be necessary 
here to allude to those of especial interest, and to trace the 
general change in the charaeter of the deposit as the Crag rises 
towards the west. 
Between Cromer and West Runton there is a decided tendency 
for the Crag to become more sandy, and also more full of shells. 
In this distance, about two and a half miles, the Chalk rises from 
extreme low-water to about five feet above that level. Tlie 
immediately overlying stone-bed,” or bed of large little worn 
flints that is always found beneath the marine Crag and upon the 
Chalk, is so firm and cemented with iron that not only does it 
show as a continuous ledge on the foreshore, but it protects the 
underlying Chalk, so that the junction can nearly always be 
examined. The smoothness and evenness of the denuded surface 
of the Chalk is very marked; for not only is there no piping, but 
even the slight hollows usually found are missing. This is 
probably owing to the absence of all pereolation, and to the unusual 
softness of the Chalk, which in this district never forms submarine 
ledges at the present day. 
Between the unworn flints of the stone-bed occur numerous 
specimens of Mya arenaria, Tellina ohliqua^ and occasionally of 
T, balthica, in the position of life—proving that we are dealing 
* Geology of the Country around CvomQV (^Memoirs of the Geological Survey), 
pp. 11-19. (1882.) 
