48 



THE WHITE RIVER BADLANDS 



are Snake Creek, Oak Creek, Little White Eiver, Niobrara 

 Eiver and Spoon Butte. 



The beds are of Lower Pliocene age and are of especial 

 stratigraphic value in that Pliocene mammals are not well 

 known in North America and the mammalian fauna which 

 the beds have yielded has helped materially in filling in the 

 gap. 



GEOLOGIC SECTION OF THE BIG BADLANDS 



Approximate estimate thick- 

 ness of the beds 



Characteristic Species and General 

 Nature of the Rock 



100 feet 



Protoceras Beds •{ 



50-75 feet 



( Leptauchenia layer; nodule-bearing, 

 ■{ pink-colored clays widely distribu- 

 I ted. 



I Coarse sandstones, occupying different 

 j levels, not continuous. 



Oreodon Beds 



100 feet 



10-20 feet 



70 feet 



Light colored clays. Few fossils. 



[ Nodulous clay stratum. Bones white. 



75-100 feet \ a , . .. . _ 



Sandstones and clays. Bones rusty 

 I colored. 



Oreodon layer; nodule-bearing, very 

 constant and widely distributed. Nu- 

 merous Oreodons and turtles im- 

 bedded in nodules. Bones always 

 covered with scale of ferruginous 

 oxide. "Red layer" of collectors. 



Metamynodon layer; sandstones, some- 

 times replaced by light colored bar- 

 ren clays. Bones usually rusty col- 

 ored. 



Reddish gritty clay, sometimes bluish, 

 Bones white. 



Titanotherium 

 Beds 



^,30 feet 



100 feet 



50 feet 



Clays, sandstones and conglomerates. 



fClays, toward the base often reddish, 



j or variegated. The prevailing color, 



however, is a delicate greenish 



1 white. Bones are always light col- 



Iored or white, sometimes rusty. 

 Clays and sands, sometimes fullers 

 earth. 



