GEOLOGICAL PAPERS. 83 



NOTES ON THE GEOLOGY OF THE ANTELOPE HILLS. 



By R. S. Sheewin, University of Oklahoma, Norman, Okla. 

 Read ( by title ) before tbe Academy, at Topeka, January 2, 1903. 



^y^HE Antelope Hills form the most conspicuous landmark of west- 

 -■- ern Day county, in Oklahoma. They are outlying remnants of 

 an old plateau, probably of Tertiary age, situated on the south side 

 of the South Canadian river, on the inside of a large bend. The dis- 

 tance of the river from the hills varies from about two miles on the 

 west to ten on the north and four or five on the northeast. In gen- 

 eral outline, the drainage of the area around the hills and inside the 

 bend of the river resembles an open fan. 



The following section was taken on the largest of the buttes : 



4. Gentle covered slope at top 25 feet. 



.3. Gray sandstone 25 " 



2. Sand or saccharoidal sandstone 30 " 



1. Long covered slope to the river 460 " 



Total 540 feet. 



On top of the hills and near them were found many pebbles of 

 flint, limestone, and several igneous rocks, including lava. The ce- 

 menting material of the sandstone is calcium carbonate. The amount 

 of it varies greatly, and it is sometimes found in concretion-like forms 

 which contain comparatively little sand. These concretions weather 

 out very unevenly, and give the edge of the sandstone the appearance 

 of being covered with stalactites. Some of them are larger than a 

 man's arm, while others are small. The soft saccharoidal sandstone 

 below the cap-rock differs from it only in having less of the cement- 

 ing material. The little that it does contain is irregularly distributed. 

 Even in the sandy slopes and in the soil lower down, there are small 

 concretions of carbonate of lime. A few scattered buffalo bones were 

 found on and near the hills, and some fragments of larger fossil bones 

 were found on the southwest slope of the largest butte. 



Locally the two hills farthest east are known as the Twin Hills, be- 

 cause they are so nearly alike, and about three miles from the other 

 four, which are called the Antelope Hills. None of them have any 

 timber except a few crooked cedars around the edges. The area of 

 the top of the largest butte is probably less than thirty acres, and the 

 total area of the tops of the group would hardly exceed sixty acres. 

 There is a small spring of good water at the base of the largest one, 

 and a larger one about a quarter of a mile from the Twin hills. 



The cap-rock of the Antelope Hills is at about the same level as the 



