BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA 

 Vol. 25, pp. 417-420 September 15, 1914 



PROCEEDINGS OF THE PALEONTOLOGICAL SOCIETY 



GEOLOGY OF THE UINTA FOEMATION ^ 



BY EARL DOUGLASS ^ 



{Presented before the Paleontological Society by H. F. Osbom January 



1.19U) 



CONTENTS 



Page 



Introduction 417 



Extent and location of the formation 418 



Divisions of the deposits 418 



Introduction" 



The deposits here discussed were called the '^^Uiiita Group" by Clarence 

 King in 1878. 



The great thickness of reddish sandstones and quartzites of the Paleo- 

 zoic of the Uinta Mountains were previously, in 1878, named ^^Uinta" by 

 Powell. It is best, therefore, •" at present to designate the deposits now 

 under discussion as the "Uinta Group" or the "Uinta Tertiary." 



The Uinta Tertiary has furnished many interesting mammalian and 

 reptilian remains, and several expeditions have been sent into the Uinta 

 Basin to collect fossils. Some of these show that at least part of these 

 deposits are newer than the typical Bridger and older than the White 

 Eiver Oligocene ; therefore the name of the group has given the name to 

 a stage in the development of vertebrate life called the "Uinta stage." 



The main area containing the Uinta Group is quite extensive, but lies 

 in one compact body and the boundaries, as a rule, are quite well defined. 

 It fvirnishes an excellent area for the study of Upper Eocene geology; 

 but there never has been a careful survey of the region, nor has there 



1 Manuscript received by the Secretary of the Geological Society .Tune ir», 1914. 



2 Introduced by H. F. Osborn. 



(417) 



