TRACING FAULTS ] 



sides, the central parts of the fracture being filled with 

 the broken rubbish. The breadth of broken material 

 may vary up to a mass of many yards. If, on the face of 

 a cliff, two sets of rocks are brought against each 



other along a steep line of junction, where they are both 

 jumbled and broken, that line will almost certainly be 

 found to be a fault (Fig. 36). But examples will be met 



fw.j6.-S.ctio. of. fcult 



with where the two sides come together with a dean 



sharp line, as if they had been sliced through with a knife. 



The inclination of the sides of the fault is termed its 



and in normal faults slopes away from the side 



which has been pushed up, or in the direction of that 



i has gone down. This is a useful fact, as it 



enables an observer to note which is the up- throw or 



down throw side of a fault. The hade ought therefore 



always to be noted, and in mining districts its angle of 



