TEETIAKIES OF THE UINTA VALLEY. 309 



to the slopes of (he Wahsatch, here, as far as our observations showed, con- 

 sisting generally of the coarse red and chocolate sandstones, with an ever- 

 increasing predominance of gravel and conglomerate material to the west- 

 ward. They occupy relatively elevated positions, and correspond so much, 

 in general lithological character, to the Tertiaries of the Wahsatch region 

 along the Weber River and northward, which have been referred to the 

 Vermillion Creek Eocene, that it seems possible that these western develop- 

 ments may belong to the same series, the more, as the present topography 

 offers no evidence of any barriers between the seas in which they were 

 deposited. 



Between the east and west branches of the Lake Fork, on the very 

 flanks of the Uinta Eange, an exposure of Tertiary beds was found, of a 

 very different character to those of the valley-terraces, which evidently 

 occupy a higher horizon, and may belong to a later series. In this case, 

 they would probably represent the western extension of the beds observed 

 in White River Valley. At this point is a quarry-like opening, where the 

 beds of the steep slopes, usually covered by vegetation and debris, have 

 been denuded by the erosion of a little mountain-stream. A thickness of 

 about 600 feet is exposed, of massive beds of coarse yellow sandstone, 

 showing some concretionary structure, and worn out by atmospheric action 

 into caves and round spire-like forms. The sandstones contain pebbles 

 of saccharoidal quartzite, both rolled and angular. Some beds are very . 

 fine-grained, of white color, with a buff striping, running into very fine 

 siliceous beds containing calcareous material, very like, in general appear- 

 ance, certain strata observed in Brown's Park. At" the base of the series 

 are some reddish strata, but none of the red sandstone and gravel beds 

 observed in the open valleys below. A singular regularity and persist- 

 ence in the jointing-planes of these beds gave the appearance of a dip, at 

 first sight, of 80° to the south; but on careful examination, the existence 

 of beds of clay and pebbles showed the actual planes of deposition to be 

 nearly horizontal, with a dip of from 2° to 5° southward. To the west of 

 this exposure, the Tertiary beds, distinguished by their horizontal stratifica- 

 tion, could be seen to extend higher up on the spurs, to a height of not less 

 than 2,000 feet above the stream-bed, at the gateway of the canon, and 



