62 SEDIMENTARY GROUPS OF THE PLATEAU PROVINCE. 



Kwa-gunt Valley. Some of the members are again exposed at the bottom 

 of the Grand Canon, where it passes the Shi-wits Plateau. 



Lower Silurian fossils have been found at the base of this group. 



EED CEEEK GEOUP. 



The Red Creek Quartzite, with its intercolated beds of hornblendic, 

 micaceous and chloritic schists, is well seen in Red Creek Canon. Other ex- 

 posures can be seen at the head of Willow Creek, a little stream that 

 comes down from the O-wi-yu-kuts Plateau, and empties into the Green 

 River midway in Brown's Park. 



GEAND CANON SCHISTS. 



This group is revealed in the depths of the Grand Canon in all its 

 great southern bends. 



EPOCHS SEPARATING THE GROUPS. 



BISHOP MOUNTAIN CONGLOMEEATE. 



The Bishop Mountain Conglomerate is found at different places to lie 

 unconformably upon every group of the table which is represented in the 

 Uinta Mountains and adjacent country. Its plane of demarkation repre- 

 sents a cessation of the movements of displacement in the region over which 

 it is found, and that the same region was planed down to a base level of ero- 

 sion, which base level was continued during the accumulation of these beds, 

 for it is believed to be a subaerial conglomerate; but should further evidence 

 prove it to be a subaqueous accumulation the plane of separation would then 

 represent an epoch of change from a period of erosion to a period of depo- 

 sition. This point will be more fully discussed hereafter. 



BEOWN'S PAEK GEOUP. 



This group in Brown's Park is seen to lie unconformably on the Uinta 

 Sandstone, and all the other Paleozoic, Mesozoic and early Cenozoic groups; 

 the plane of demarkation, therefore, represents an epoch of change from a 

 dry land to a submerged condition. The area over which it was deposited 

 within the region of my study is of small extent, but the beds are known 



