. 6 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY 
fault escarpment, and that the weaker Cretaceous strata were thus ex- 
posed ina belt between the fault line and the retreating Paunsagunt 
cliffs ; the drainage of the Cretaceous belt at this time being very prob- 
ably effected by headward obsequent prolongations of the originally 
short west-flowing consequents, whereby the east-flowing consequents on 
the Paunsagunt had been progressively beheaded. In the second cycle, 
it is reasonable to infer that Kanab creek gained possession of the weak 
Cretaceous belt by headward erosion from the south, and that the east- 
flowing consequents on the Paunsagunt were thus still further undercut 
and beheaded. 
There is some independent evidence of the correctness of these sup- 
positions. Where the road from Panguitch to Kanab crosses the divide 
between the Virgin and Upper Kanab creek a little south of Ranch, 
there is a sheet of basalt that seems to spread horizontally across the 
FIGURE 3. 
General cross-section three miles south of Upper Kanab. 
fault line, covering Tertiary and Cretaceous strata indifferently, as in 
Figure 3. It is thus suggested that at the time of the basalt eruption 
the effects of faulting had been locally obliterated, and this gives war- 
rant for the first cycle of erosion. To-day the basalt forms an upland 
affording a fine view in nearly all directions, and the valleys are eroded 
several hundred feet beneath it; and this gives warrant for the second 
cycle of erosion. Moreover, the headwaters of Kanab creek are to-day 
extending their drainage area towards the north and east, and this sug- 
gests that they have been doing so in the past ; in other words, Kanab 
is a growing subsequent streain, successfully invading the drainage area 
of its neighbors. 
In view of so great a transformation from the topography supposedly 
initiated by the faulting to the existing topography produced by ‘erosion, 
it seems necessary to give the Sevier fault a date somewhat earlier than 
late Tertiary time: yet it should not be thrown too far back toward the 
