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524 GEOTECTONIC (STRUCTURAL) GEOLOGY. [Boox IV. 
wall-like mass of frazmentary rock, known as “ fault-rock.” Where 
_ a dislocation has occurred through materials of very unequal hardness, 
such as solid limestone bands and. soft shales, or where its course has 
been undulating, the relative shifting of the two sides has occasionally 
brought opposite prominences together so as to leave wider inter- 
spaces (Fig. 301). The actual breadth of a fault may vary from a 
mere chink into which the point of a knife could hardly be inserted, 
up to a band of broken and often consolidated materials many yards 

Fic. 252—Srction oF Favutt witu INVERTED BEDS ON THE Down-THROW SIDE. 
wide. Where a fault has a considerable throw it is sometimes flanked 
by parallel small faults. ‘The occurrence of these close together will 
obviously produce the appearance of a broad zone of much fractured 
rock along the trend of a main fissure. A line of disturbance may 
consist of several parallel faults of nearly equal magnitude (Fig. 255, 
Section 3). | 
Inclination of Faults.—Faults are sometimes vertical, but are 
generally inclined. The largest faults, that is, those which have 
the greatest vertical displacement, slope at high angles, while those 

— 
Fie. 253,—Sxcrion or Group or Favurs, Coast or GLAMORGANSHIRE, WEST OF 
Lavernock Point (B.). 
mmm, three adjacent faults by which the inclination of the strata is shifted and some 
of the beds are crumpled ; a, dolomitic limestone and marl; b, ¢, d, e, f, dolomitic 
limestone; g, dolomitic conglomerate; h, beds corresponding with those on the left - 
1, Lias, thrown in by a “reversed” fault, ; 
of only a few feet or yards may be inclined as low as 18° or 202. 
The inclination of a fault from the vertical is called its hade. In 
Fig. 254, for example, the fault at B, being vertical, has no hade, but 
that at A hades at an angle of 70° from the vertical to the left hand. 
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