94 THE UNIVERSITY OF OKLAHOMA 



changing the subdivision of the Glenn formation and giving some 

 new suggestions in regard to correlation of its parts. After ex- 

 tended studies at the eastern end of the Arbuckle mountains, G. D. 

 Morgan in Circular No. 12 of the Oklahoma Geological Survey 

 places the Franks conglomerate below the center but not at the 

 base of the Pennsylvanian series. 



XVI. A STUDY OF SOME CONGLOMERATES NEAR 

 THE EASTERN LIMITS OF THE RED BEDS OF 

 OKLAHOMA 

 O. F. Evans 

 From the Oklahoma Geological Survey and the Department of 

 Geology of the University of Oklahoma. 

 The conglomerate described in this paper was studied in the 

 following localities. Twelve miles east of Norman, six miles east 

 of Moore, and over an area several miles square northeast of Jones, 

 Oklahoma. The same conglomerate is found near Guthrie, Okla- 

 homa, and is also known to extend for several miles northeast of 

 Jones. It is always found associated with red sandstones and is 

 sometimes interbedded with them. It is composed of concretions 

 and fragments of sandstone mixed with sand. The cement is prob- 

 ably calcium carbonate as it effervesces freely with acid. The con- 

 glomerate occurs in lenses from a few inches to four or five feet 

 thick. In some places the lenses are of considerable extent and 

 give somewhat the appearance of being continuous. It is some- 

 what more resistant to weathering than the associated sand stone 

 and this results in benches and butte-like forms wherever there has 

 been considerable erosion. The lenses arc found through a section 

 of the sandstone nearly 100 feet thick and often appears to be 

 in horizons about 20 feet aparl. As many as four of these apparent 

 horizons were found in making a survey near Jones. The tendency 

 of the conglomerate to ho!d up erosion and form buttes and 

 benches has led in some cases to attempts being made to use it in 

 running oil structures. 



It seems to be impossible to distinguish the lenses apart at dif- 

 ferent elevations and it is quite probable that they do not occur In 

 definite horizons but are scattered here and there through the sand- 

 stone. They were undoubtedly laid down at the same time as the 

 surrounding sandstone. They were probably deposited in a shallow 

 sea near a shore of massive sandstone to the east. As this sand- 

 stone eroded and broke up the coarser material was gathered into 

 lens-hke masses by water currents and these lenses covered by sand 

 that was later consolidated. 



