RED BEDS BETWEEN WICHITA FALLS AND LAS VEGAS 255 



glomerate followed from farther east forms the floor of the valley; 

 the upper part of the Triassic is exposed in the walls of the mesa 

 beneath the capping of Dakota Cretaceous and the Morrison 

 formation (Lee), and the lower part is seen in the valleys of the 

 streams. Beyond Cabra Spring (a single ranch house located near 

 the middle of the Corazon Topographic Sheet) the Conchas River 



Fig. 8. — Red clay in the walls of Bull Canyon just south of Montoya. This is the 

 portion of the Triassic above the conglomerate layer which forms the shelf extending 

 north from the foot of the Staked Plains. 



has cut a deep gorge through the heavy sandstone and conglomerate 

 into a heavy bed of white sandstone (40-50 feet) of a local char- 

 acter. Beneath and partly within this sandstone is a lense of 

 dark-red and mottled clays and shales, much distorted and streaked 

 with greenish clay and a greenish conglomerate of small pebbles. 

 This is the lowest bed of the Triassic that was seen and it so much 

 resembles the Double Mountain that I at first thought that it must 

 be Permian; but the discovery of Unios in the layer of greenish 

 conglomerate revealed its Triassic age. This makes it altogether 

 probable that nothing below the base of the Triassic appears between 

 Montoya and Las Vegas. 



Ascending to the top of the mesa by the difficult road at the 



