664 T - w - STANTON 



Rio Cimarron. — East of Garrett P. O. on the Cimarron in western 

 Oklahoma, the Red Beds are exposed with a slight westerly dip which 

 carries them below the surface near Garrett, and in that neighbor- 

 hood the section extends up to the top of the Dakota. 



The section generalized from observations covering a few square 

 miles is as follows: 



i. Massive, coarse, cross -bedded gray and brown sandstone 



of the Dakota 150 feet 



2. Dark shales with layers of brown flaggy sandstone and bands 

 of somewhat calcareous yellow sandstone with Comanche 



fauna ; 50 to 60 " 



3. Coarse, brown or gray cross-bedded sandstone with irregular 

 bands of pebbles, apparently unconformable on the under- 

 lying stratum 4 to 15 " 



4. Variegated shales, gray sandstones and bands of siliceous 

 limestone, referred to the Morrison, not well exposed. 



Thickness probably less than 100 " 



5. Red Beds. 



The Comanche horizon has yielded a varied fauna which is clearly 

 the same as the Washita fauna that has long been known at Mesa 

 Tucumcari, New Mexico, in northern Texas, and in the Kiowa shales 

 of southern Kansas. The following species have been identified: 



Gryphaea corrugata Say 

 Ostrea subovata Shumard 

 Ostrea quadriplicata Shumard 

 Plicatuld incongrua Conrad 

 Inoceramus comancheanus Cragin 

 Gervilliopsis invaginata White 

 Trigonia emoryi Conrad 

 Protocardia multilineata Shumard . 

 Pholadomya sancti-sabae Roemer? 

 Anchura kiowana Cragin ? 

 Turritella seriatim-granulata Roemer 

 Hamites Jremonti Marcou ? 

 P achy discus brazoensis (Shumard). 



This horizon was traced with practical continuity westward up 

 the Cimarron to Folsom, New Mexico, a distance of about seventy-five 

 miles across the strike. Its lithologic features show little variation 

 and its thickness is never less than fifty feet nor more than one hundred 



