SW. 
GUIDEBOOK OF THE WESTERN UNITED STATES. 
Pikes Peak 
Figure 11.—Profile section through Pikes Peak and Cascade, showing the relation of the mountain peak to the lower land (peneplain) on either side. 
surface of this plain is the deep 
and perfect disintegration of the 
granite rock which composes all 
this country. No ledges of rock 
can be seen, and the soil is made up 
largely of small fragments of gran- 
ite broken up by the action of the 
weather. This even surface is 
well shown in Plates XV, A (p.31), 
and XXIV, A, and its relation 
to Pikes Peak is shown in fig- 
ure 11. 
This plateau can be traced north- 
ward at least as far as Denver. It 
is the result of long exposure to the 
action of the weather and the cut- 
ting of the streams when the entire 
region was at a much lower level 
than it is to-day—so low, in fact, 
that the streams could cut no 
lower—and it remained in this 
position so long that most of the 
hills and other inequalities of the 
surface were worn away and the 
region was reduced to a plain as 
truly as the country about Denver 
and Colorado Springs is a plain to- 
day. That was long, long ago, as 
man measures time, even before 
man was there to see any of 
the operations that produced the 
change. 
Then came a slow but steady up- 
lift of the mountain region and 
probably also of the plain, until 
the land reached its present height 
above sea level. Such an uplift 
accelerated the streams, and they 
soon cut deep canyons—such as Ute 
Pass and the canyon of Cascade 
Creck—in the surface of the pla- 
teau, until to-day it is level only as 
one looks across broad tracts of its 
old surface and at a distance so 
great that the details fade and the 
plain looks as it once did before 
