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PHYSICAL GEOLOGY 



downthrow sides, and it is important to note that in normal 

 faults the plane of slipping slants down away from the up- 

 throw side. 



FIG. 53. Fissility in highly tilted beds of slate. (Gilbert, U.S. Geol. Sun.) 



Reversed faults. Where the rocks have been compressed 

 instead of stretched, the strata may be broken as well as 

 folded. Thus the second type of faults is produced. In such 

 cases the lower and therefore older rocks are shoved up and 

 over the higher and younger. This is the reverse of the con- 

 dition in a normal fault, hence the name. Some reversed 



