DAVIS: THE WASATCH, CANYON, AND HOUSE RANGES. 53 
irregularity and many irregular valleys would be eroded in the higher 
Strata. If we now turn to the facts it is found that the higher gray 
limestones of Swazy peak have a border that pays little attention to 
the scarp of the fault block. The border of the higher limestones 
Stands well to the west in the peak, which rises only two or three miles 
ack from the face of the range; the border recedes southeastward 
(and probably northeastward also) on the flanks of the peak, and 
nearly reaches the eastern base of the range by the northern road. 
he slopes of the range east of the peak are irregularly dissected by 
valleys that show basset edges, as in figure 28, with unusual frequency. 
These features suggest very strongly that the general outline of the 
Upper limestones must have been deter- 
mined by extensive erosion in the earlier 
cycle, before block faulting occurred. The 
sray-and-slate colored limestone, on the 
Other hand, advances to the great promon- Fra. 28.— Valley in the back 
tories of the Swazy mass, and these prom- slope of the Swazy mass, with 
Ontories stand in so accordant a relation to De er Ed ordinary 
outcrops; looking north. 
the western base of the range that it must be 
Supposed they were determined by post-faulting erosion. It is satis- 
actory to note that these conclusions accord with those gained from 
the features of the Sawtooth mass. For the present, Swazy peak has 
generally graded slopes; but when the ravines of the western escarp- 
ment are gnawed farther back into the range, some of them will 
undercut the base of the peak and sharpen it into huge cliffs that 
May outrival those already sharpened in the Sawtooth mass. 
he absence of the upper gray limestones from the eastern slope of 
the Smoothback mass cannot be accounted for by erosion during the 
relatively short part of a cycle that has elapsed since the block fault- 
Ing, but it may have been accomplished naturally enough in the pre- 
aulting cycle. In such a case the Smoothback area may then have 
“en a peneplain underlaid by the more or less shaly intermediate 
members of the rock series. Since the block faulting the shales have 
een mostly swept off, leaving a rather-smoothly stripped back slope, 
from which this part of the range is given its provisional name. 
GENERAL CONSIDERATIONS. 
If the conclusions now reached are taken to apply to the Basin 
ranges as a whole, the following general statement may be made. 
he region appears to have reached a stage of late maturity or early 
