FEONT EA^GE. 393 



SECTION IV. 



NOETHEEN WAHSATCH EEGION. 



BY ARNOLD HAGUE. 



Feont Range. — To the nortli of tlie lower canon of the Weber, the 

 front ridge of the Wahsatch Range presents the same bold escarpment 

 toward the west as it does farther south, but its summits are less elevated, 

 and the ridge itself comparatively narrow, being bounded on the east by a 

 series of deep, broad valleys. Geologically, however, the Wahsatch Range 

 in this portion is much wider than to the south ; the great , conformable 

 series of lower beds extending in broad anticlinal and synclinal folds into 

 the elevated plateau country to the east of Cache Valley. 



In the geological structure of the main front ridge, the same general 

 type of an anticlinal fold, whose western member has been broken down 

 and carried away, is maintained as heretofore; but the exposures of the 

 underlying Archaean rocks are less considerable and less frequent, showing 

 that the original Archaean body, like that of the present day, became 

 gradually lower toward the north, and, instead of following the eastern 

 borders of this body in comparatively continuous folds, the strata of the 

 overlying, unconformable Palaeozoic formations are broken by a series of 

 numerous faults at right angles to the trend of the range, on the north side 

 of which, as a general rule, the beds have been raised and moved back to 

 the eastward. While the faults increase immensely the difficulties of tracing 

 out the structure, in detail, of formations whose general petrological charac- 

 ters are so similar from one horizon to another, their general outlines may 

 be detected by the eye trained in the study of geological structure, even 

 from the Salt Lake Valley, at a distance of many miles from the range. 

 Particularly is this the case in the extremely broken region back of Ogden 

 City, where, on the face of the range, may be traced, by the breaks in the 

 lines of stratification, the position of the principal fault-lines, which have 

 been indicated on the map. 



