CLAY AND ITS MODE OF OCCURRENCE. 



i5 



Where a bed is not sufficiently elastic to bend under pressure, 

 it breaks, and if, at the same time, the beds on opposite sides of 

 the break slip past each other, faulting is said to occur. When 

 the breaking surface or fault plane is at a low angle, one por- 



Fig. 4. 



Section showing strata broken by a series of parallel fault planes. 



Fig. 5. 



Strata broken by a fault plane of low inclination. 



tion of the bed may be thrust over the other for some distance. 

 In other cases the displacement may amount to but a few- 

 inches. Figs. 4 and 5 represent sections in faulted strata, 

 and in these it will be noticed that every bed terminates 



