98 



GEOLOGY OF THE DENVER BASIN. 



which can be suggested. It is nol intended, however, that this shall pre- 

 clude the acceptance in the future <>t' any other grounds upon which it 

 may be possible to establish a still more satisfactory explanation of the 

 phenomena forming the subject of this section. 



Manner in which the forces of elevation have locally manifested themselves. At Yai'ioUS lioillfs 



along the base of the Colorado Range occur strongly pronounced local 

 peculiarities of structure, either faults, or folds of varying shape and char- 

 acter, both secondary as to the general uplift of the range. It is highly 

 probable that these structural peculiarities are attributable to the general 

 forces of elevation that are acknowledged to have been in action throughout 

 the several geological periods here represented. 



The unequal distribution of, or resistance to, the general force of elevation. S^till tui'tllel', it llia\' 



unhesitatingly be granted that the general force of elevation or the resist- 

 ance opposed to it has been more or less unevenly distributed from point 



l'i., -t I llustral inn nf uiHDiiforiiiily 



to point, and has acted, not always at an absolutely right angle to the axis 

 of the range, but diagonally to it, in one or more directions at the same 

 time. Its direction has in fact varied according to circumstances. 



The development of the post-Niobrara fold. In tllC present area tile distribution alld 



directions of this force up to immediate post-N'iolirara time had been such 

 as to eventually bring into existence the fold of the general character 

 represented in the profiles, and in fig. 4. 



An analysis of this distribution and its effects shows that, of the 

 various components of this force, the major, which exceeded all the others 

 combined, was that acting in the general elevation of the range and directly 

 against its axis — that i>, for the eastern base, with the arrows A (fig. 4), 



