
158 STRUCTURAL AND FIELD GEOLOGY 
Asa general rule, normal faults are more or less closely 
related to the leading or dominant rock-foldings of the 
district in which they occur. Hence they can usually be 

FIG. 35.—NORMAL FAULT, NOT ACCOMPANIED BY DISTORTION, 
described as Dip-faults and Strike-faults, in this respect 
recalling the systematic arrangement of the joints char- 
acteristic of sedimentary strata. It must not be supposed, 
however, that the coin- 
cidence of faults with 
dip and strike is always 
close. The most ‘that 
can be said is that they 
trend approximately in 
those directions. Fre- 
quently, however, they 
Fic. 36.—NORMAL FAULT, ACCOMPANIED traverse the rock-folds 
BY DISTORTION. obliquely, just as joints 
do, and sometimes it is difficult to detect any system or 
arrangement among them. Nevertheless, the larger faults 
tend, on the whole, to coincide more or less closely with the 
geological structures referred to—a relation which can hardly 
be said to characterise the smaller or less important dis- 
locations. In these and other respects, therefore, normal 
faults have many analogies with the joints of sedimentary 
accumulations. 
Dip-faults have a characteristic effect upon the outcrops 
of rocks, which they appear to shift. This is well seen when 
such a fault crosses an escarpment, the long line of which 
is suddenly interrupted and shifted forward or backward, 
according to the position from which we view it. This 
advance or retreat of the outcrops along a line of dip-fault 
must not be confounded with the lateral displacement already 


