from the Comanche to the Dakota Cretaceous. 171 



Section I. 



\ mile south of Greenleaf's ranch. 

 No. Feet. 



3. Small Tertiary knob resting unconformably on No. 2.. 15-95 

 %. Bluish clay shales, weathering white, containing numer- 

 ous clay-ironstone, geodic, concretions, breaking with 



a conchoidal fracture into small fragments with sharp 

 edges. One stratum of brown sandstone 4 inches 

 thick contains marine bivalves and shows ripple 

 marks on its surface. The clays contain layers of 

 sandy shales in the upper part. The Spring Creek 

 clays 50-80 



1. Typical upper Kiowa bluish-black to yellowish shales 



with selenite crystals and numerous Gryphaea, grad- 

 ing insensibly into No. 2 . _ _ 30-30 



Section II. 

 \ mile west of Greenleaf's ranch. 



4. Tertiary sandstone on top of bluff 10-90 



3. Yellowish brown sandstone, usually distinctly stratified, 



but occasionally massive and cross-bedded, containing 

 bands and concretionary pockets of dark brown or 

 black clay-ironstone, breaking with a conchoidal frac- 

 ture; eroded in upper part. The Greenleaf sandstone 40-80 



2. Bluish-white clay with clay-ironstone concretions. Slope 



mostly covered. The Spring Creek clays 20-70 



1. Black to bluish Kiowa shale to bed of river, with occa- 



sional Gryphaea. Slope usually covered 20-20 



Section III. 



On Spring Creek, 1 mile south of the Kirby (or C. W.) ranch. 

 No. Feet. 



6. Tertiary slope to top of divide 50-200 



5. Dark brown massive sandstone, often cross-bedded, with 



many white pebbles and large nodular concretions, 

 which sometimes attain the size of 2X3 feet. No 

 fossils noticed. The Reeder sandstone 20-150 



4. Yellowish clays, arenaceous below, becoming reddish 



above and containing several strata of light yellow 

 sandstone. The characteristic fragments of clay- 

 ironstone color the slopes. The Kirby clays 20-130 



3. Light gray to yellowish sandstone often distinctly strati- 



fied but sometimes cross-bedded and massive with 

 bands and pockets of the characteristic dark brown 

 or black clay-ironstones. The Greenleaf sandstone.. 55-1 10 



2. (c) Yellowish to bluish clays, weathering white, con- 



taining, in lower part, bands of spongy clay-ironstone 

 like (6), which weather into small, irregular, pinkish 

 lumps and give a red tint to the slopes 20 



