South Dakota School of Mines 



35 



Geologic Section of the Big Badlands. 



Approximate estimate thick- Characteristic species and general 

 ness of the beds. character of the rock. 



Protoceras Beds 



^ Leptauchenia layer; nodule-bearing, 

 100 feet- pink-colored clays widely distribut- 

 ( ed. 



r n 7 r f + j j Coarse sandstones, occupying different 

 levels, not continuous. 



Barren Clays 100 feet 



(Now included with the Light colored clays. 



Oreodon Beds.) 



75-100 feet 



j Nodulous clay stratum. .Bones white. 



Sandstones and clays. 

 colored. 



Bones rusty 



Oreodon Beds 



10-20. feet t 



5 feet 



Oreodon layer; nodule-bearing, very 

 constant and widely distributed. 

 Numerous 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 ibluish. 

 Bones white. 



(Now included with the j Mingled remains of Titanotherium, 



Oreodon Beds.) 20 feet",. Aceratherium and Mesohippus. 



3 feet ■) 



r 



10 feet ! 

 Titanotherium Beds 1 



5 feet 



Clays, sandstones and conglomerates. 



Clays, toward the base often reddish, 

 or variegated. The prevailing color, 

 however, is a delicate greenish 

 white. Bones are always light col- 

 ored or white, sometimes rusty. 



