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DAVIS: THE PLATEAU PROVINCE OF UTAH AND ARIZONA. 39 
half the length of the escarpment, as it is seen from the lava-capped hill 
where the Panguitch-Kanab road crosses the divide between Virgin river. 
and Kanab creek ; and all these cliff faces are evidently the result of a 
revival of erosion in the Kanab headwaters by which the tree-covered 
slope, formerly continuous, has been locally attacked and worn away, 
The once subdued escarpment has thus been here and there eroded 
back into cliff-walled amphitheatral recesses, whose pink faces are seen 
between the forest-covered slopes that still record an earlier stage of 
erosion. 
The revival of stream erosion by which the Pink cliffs are thus 
locally refreshed may be associated with the revival of degradation by 
which the present graded floor of Upper Kanab creek has been lowered 
beneath the level of earlier grades, whose remnants may be clearly seen 
stretching southwestward beneath the outermost point of Paunsagunt 
plateau. Both these consequences of revival may be plausibly associated 
with the elevation of the region by which the canyon cycle was intro- 
duced ; and the relatively small amount of work here accomplished in 
the new cycle as compared to the much greater work accomplished in 
the same period of time by the Colorado, the trunk river of the region, 
may be reasonably ascribed to the normal delay of small headwater 
streams in taking cognizance of uplifts, as compared to the promptness 
with which advantage is taken of such opportunities by the main 
rivers. 
The upland of the Paunsagunt plateau is drained by the consequent 
northeast-flowing headwaters of the East fork of the Sevier. When the 
upland was first formed, the streams must have headed decidedly 
farther south than they do now; for they have been significantly 
shortened by the recession that the Pink cliffs have suffered during the 
excavation of Upper Kanab valley. The indentations in the scalloped 
sky line of the cliffs mark the present heads of these shortened 
streams. 
Tue VALLEY OF THE VIRGIN. — The towers and temples of the Virgin 
canyon in the Triassic terrace of the High plateaus have been described 
in glowing language by Dutton (b, Chap. III.). As in the Colorado 
canyon, the cross-section of the Virgin canyon exhibits a perfect 
response of form to structure, and an absence of benches independent of 
structure such as would be expected had there been a significant pause 
during the elevation in consequence of which the canyon has been 
eroded. At Rockville, a few miles below the junction of the North and 
East forks of the Virgin, the river flows in the middle Permian clays; 
