132 GUIDEBOOK OF THE WESTERN UNITED STATES. 
compared with most of the other events in geologic history it was 
very recent. 
The broad bench made by the lava at the lower level just men- 
tioned is well exhibited near Corva, where the eastbound track 
joins the old line. Fairview is a siding on this 
bench. A short distance beyond Fairview is a cut in 
a low cinder cone that shows that there was a vol- 
eanic vent at this place from which may have issued 
some of the lava on the lower bench. Two miles farther west is a 
long cut in cinders, including numerous bombs of various sizes. 
About 4 miles west of Fairview there are excellent views of the 
edge of the high plateau extending off northwestward. The white 
ledges of Kaibab limestone appear in places, capped by the black 
lava at the summit of the plateau and underlain by the Coconino 
sandstone extending down some distance to the lava-covered bench 
above mentioned. The extension of the cliff to the southeast is also 
visible but less plainly. 
Fairview. 
TT tion 5 92. ‘eet 
Kansas City 1,315miles. 
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At milepost 399, 5 miles west of Fairview, there are long cuts in 
cinders with bombs, beyond which the railway descends westward in 
long sweeping curves that extend nearly to Ash Fork. At the foot of 
this down grade there is a wide valley trending northwest and occu- 
pied largely by lava which has flowed from many local orifices, in 
most places marked by cinder cones. A section showing the general 
relations in the descent of the great escarpment east of Ash Fork is 
given in figure 31. 
This descent is the first in a series of great westward-facing steps 
formed by the thick pile of sedimentary rocks constituting the plateau 
region of western Arizona. These rocks are shown in cross section in 
the Grand Canyon, and in the westbound journey the traveler sees, 
beyond Williams, the same succession that is revealed in the descent 
into the canyon from the rim. The first step is the western edge of 
the Kaibab limestone which caps the plateau and finally terminates 
in the Aubrey Cliffs. The second great step consists of the Grand 
Wash escarpment, Music Mountain, and the cliffs south of Peach 
Springs, in which the western edges of the lower part of the Redwall 
