2l8 EXPOSURE IN THE KEUPER CLAYS AND MARLS. 



local succession of beds. Few good examples occur locally — 

 except, of course, in the coal measures —where faults are to be 

 well seeHi in section. This is a very good example, although it 

 is hardly possible to estimate the extent of the disturbance. It 

 is most probably connected with the fault shewn upon the 

 Geological Survey Map as passing through Derby, the line of 

 fault in this exposure passing in a north-westerly direction. The 

 direction of the section is shewn. On the west side of the fault 

 the beds dip in an easterly direction at an inclination of 28° or 

 more, and on the east side they dip in the same direction at an 

 angle of 13°, becoming horizontal in about 100 yards from 

 the fault. Minor faulting and contortion are, as might be 

 expected, common in the immediate neighbourhood. The 

 section is 40 or 50 feet in height. The smaller section to 

 the north-west is still more interesting. It is shewn in Figure 2. 

 To the south the beds are very nearly horizontal, while for a 



SSv/ ^^^ 



Fig. 2. 



short distance on the north side of the fault they are nearly 

 vertical, passing to a dip of 45° in a north-easterly direction 

 in the space of a few yards. This section is 10 or 12 feet high, 

 and exhibits the peculiar re-curving of the beds shewn in the 

 figure. These bends are well seen in the grey marls, which are 

 here and there fractured. In my opinion these are due to the 

 passage of ice from the high ground which rises in a graceful 

 amphitheatre some few hundred yards to the south and is 

 capped by Boulder Clay, of which exposures may be seen 



