THE TRIASSIC PERIOD. 



21 



tion of dip. For a given throw, the horizontal shifting is greater, the less the 

 Jip and the greater the amount of the degradation of the upthrow side. 



Fig. 327. — Same as Fig. 326, after being faulted along the strike, and after planation 

 The several layers are repeated at the surface. 



3. Let the same series of beds be assumed to be affected by an oblique fault. 

 Let the plane of the fault be east-northeast by west-southwest (along GH, Fig. 

 325) and the upthrow on the south-southeast side. After erosion has reduced 

 the surface to a common level, the trap sheet will outcrop as shown in Fig. 331; 

 that is, the outcrop of the trap is offset with overlap. Had the upthrow been 

 to the north-northeast, the outcrop would have appeared as in Fig. 332; that 

 is, the outcrop of the trap would have been offset with a gap. Had the faulting 

 been along the line EF, Fig. 325, the result would have been illustrated by Fig 

 333, in case of upthrow to the northeast. 



4. If, instead of having a constant dip to the east the strata were slightly 

 deformed, that is, thrown into broad synclines and anticlines, the phenomena 



Fig. 328. — Same as Fig. 326, after faulting with downthrow at the right. When 

 erosion has reduced the surface to A B certain strata, as t , fail to appear at the 

 surface. 



would be slightly different. If such a series as the Xewark, dipping to the east, 

 be affected by a broad syncline, any given layer, after base-leveling, will not 

 outcrop in a straight line, but in a curve (Fig. 334). If the deformation had 

 been an anticline instead of a syncline, the curve would have been in the oppo- 

 site direction; that is, thj outcrop curves away from the prevalent e.i t j n L .ie 



