TOPOGRAPHY OF CENTRAL WYOMING 



the most conspicuous topography to be seen on the Piedmont 

 plains. No vegetation obscures them; there is nothing m this 

 country of magnificent distances to hide the sweep of these 

 natural ramparts as they wind back and forth across the country. 

 The softer rocks are quite fully removed as a rule, leaving the 

 depressions characteristically found where hard and soft rocks 

 alternate. The classic area of anticlines and synclines in 

 the Appalachian system of mountains is not only equaled but 

 excelled by those of Wyoming. There is a general tendency 

 in these smaller folds to be unsymmetrical; ordinarily the 

 steepest side is most completely removed, leaving the gentler 

 slopes standing as escarpments. 



A fine example of this feature is seen at Aurora, where a 

 plunging anticline has had its steepest side removed, while 

 the less abrupt slope stands as an escarpment, several feet high, 

 in which lie the dinosaur beds made famous by the researches 

 of Marsh and others. 



So well dissected is this particular anticline that a subse- 

 quent lake lies in its axis. 



The PLAINS: On passing away from the mountains 

 the folds gradually disappear, and the strata assume either a 

 horizontal position or they are inclined in some definite direction, 

 ordinarily away from the mountains. As a rule the strata are 

 monoclinal in this section of Wyoming, and as is usual in 

 such conditions the region is characterized by escarpments and 

 dip slopes. These features are especially prominent in the neigh- 

 borhood of streams, where subsequent erosion has had an 

 opportunity to work back along the strike of the rocks and 

 develop the escarpment feature. Away from the drainage 

 lines the plains are characterized by simplicity of topography, 

 though this depends largely on the nature of the underlying 



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