THE SANTA FE ROUTE. 65 
_ At Rayado the front of a high mesa is conspicuous about 8 miles 
west of the railway. It is capped by lava (basalt) and is an out- 
lying portion of a widespread sheet of lava that caps 
Rayne; the broad mesa or plateau to the south and west. 
behiratcds: fet. South of Colmor the line gradually approaches the 
Kansas City 721 miles. east end of this plateau and at Wagon Mound passes 
through a gap in it. The mesas in this vicinity are 
Colmor. not as high as those at Raton Pass, but as they rise 
eee feet. several hundred feet above the adjoining plains they 
ansas City 725 miles. @F@ prominent topographic features. Near Wagon 
Mound the lava is at two levels, representing two 
stages of outflow, but that at the lower level is of small extent. 
The lava covering the higher mesas came from vents to the west, 
probably in large part from the Ocate — pe volcanic cone, the 
location of which is shown on sheet 11 (p. 6 
Wagon Mound is one of the old sca on the Cimarron branch 
of the Santa Fe Trail, which came southwestward from a point near 
Dodge, Kans. Two monuments.a few rods east of the 
Wagon Mound. railway station show the line of the old highway. 
Firestion $11 St. This branch of the trail crossed the line of the railway 
opulation 1,983.* é . 
Kansas City 741 miles. 2 Short distance south of the station and passed 
southwestward to Fort Union, where it joined the 
other branch, which came through Raton and Cimarron and over the 
volcanic mesa west of Colmor and Wagon Mound. For a long time 
there was a Mexican customhouse at this place. Its name is derived 
from the resemblance of one of the peaks near by to a wagon top, 
when seen from points far to the northeast. 
The relations of the two lava sheets are well exposed about Wagon 
Mound. The higher sheet reaches many miles west and northwest, 
as well as along the top of the narrow ridge extending 11 miles east 
of the village. This sheet is about 100 feet thick and lies on a plat- 
form of Pierre shale that was originally the floor of the valley down 
which the lava flowed. Subsequent erosion has cut away the adjoin- 
ing lands to much lower levels and considerably diminished the extent 
of the lava sheet by undermining its edges. These edges now present 
steep cliffs, in places exhibiting columnar structure and having at 
their bases talus or piles of loose fragments. The softness of the 
underlying shale greatly facilitates the breaking down of the edges 
of the lava sheets, and in places there are extensive landslides 
where huge slivers of the hard lava have been let down in this way. 
Leaving Wagon Mound the train passes across a narrow tongue of 
the lower lava flow and a short distance farther south crosses a wide 
valley from which there are excellent views of the high lava-capped © 
mesas to the north. The high ridge known as the Turkey Mountains 
