140 



NATURAL RESOURCES SURVEY 



"Carbonaceous Shale, Seven Lakes Oil Region." 



Aside from these low, mound-like hills this region is barren 

 of any vegetation except a scattering praire grass, whose 

 scantiness leaves the unprotected soil open to the attacks of 

 the wind which strip it from every available surface and heap 

 it about the giant Gutierrezia bushes making the surface of 

 these plains in some places very rough and hurnmocky. 



As the descent is made from the crest of the Divide west- 



" Aridity and Erosion Continental Divide." 



