186 
THE GRAND CASON DISTRICT. 
displacements of the district — viz., the turning down of the edges of the 
thrown beds in the vicinity of the fault-plane. This is revealed very strik- 
ingly in Stewart’s Canon at the elbow where it turns abruptly to the west 
to join Kanab Canon. It is also seen upon the east side of the outlying- 
mass called Powell’s Plateau, which is separated from the Kaibab by a 
gorge about 1,200 feet deep. One of the steps of the fault cuts through 
this gorge, and the edges of the beds upon the west side are seen to be 
turned down. The same feature is observed in the extension of this fault 
southward into the mazes of the canon, and it is revealed in tlie great 
buttes and in the plinth walls of the cloisters, which fill the ample expanse 
of the chasm. 
The plateau mass between its bounding displacements is very nearly 
horizontal. Not quite so, however. The strata are just perceptibly arched 
in a broad anticlinal swell. The dip, however, even near the edges, where 
it is a maximum, does not exceed 2°, until (upon the eastern side) the influ- 
ence of the monocline is felt, and then the sti-ata suddenly turn down at a 
great angle. It was for a time suspected that the basin of De Motte Park 
was the result of the dropping of a wedge-like mass between two faults, 
but more careful study renders it certain that it is an ancient valley of 
erosion. 
The continuation of the Kaibab Plateau upon the southern side of the 
Grand Canon has no definition except upon the east. The fault which has 
already been alluded to gives rise to a slope which gradually becomes a 
high and abrupt cliff facing northeast and forming the eastern boundary of 
the plateau. Westward the platform declines by a very gentle slope, and 
grades into the general expanse of the Colorado Plateau without any line of 
demarkation. 
The altitude of the Kaibab at the highest point is about 9,300 feet 
above the sea. From De Motte Park northward it slowly declines. The 
altitude of the southern portion above the Paria or Marble Cation platform 
lying eastward is from 2,700 to 3,600 feet. Its altitude above the Kanab 
platform on the west is very variable, but ranges from 1,000 to 2,300 feet, 
according to the places in close proximity which are compared. 
Neglecting the minor inequalities, the general surface of the plateau 
