Mesozoic and Cenozoic Geology and Paleontology. 115 
geniously mixed with the soil around, so as to make it appear that they 
came from the decomposition of the sandstone. 
Along Bear river, in Utah, from Bear River City to Evanston, the 
hills on either side are occupied by the nearly horizontal beds of the 
Wasatch Group. The greater part of Bear river plateau is covered 
with a considerable thickness of these beds, which are in general rather 
coarser and more conglomeratic than those of the Aspen plateau. Its 
summit varies in width from 2 to 4 miles, beyond which to the east- 
ward these beds are exposed in the deep canons of Woodruff, Randolph 
and Saleratus creeks, from 2,000 to 2,800 feet in thickness. 
He found the Savory plateau region covered, principally, by hori- 
zontal beds of the North Park Tertiary, which he referred to the Plio- 
cene, and which, as proved by exposures in the deeper cuts, on its 
northern edge, overlie the upturned edges of Cretaceous and earlier 
beds, while the higher portions of the ridges are capped by remnants 
of the Wyoming conglomerate. The best exposures are found in the 
open valleys at the heads of Savory and Jack’s creeks, and on the 
pass between the Archaean body of the Grand Encampment mountains 
and the Savory plateau. A thickness of not less than 1,000 feet of 
these beds is here exposed, which is made up in the upper portion of 
a thickness of about 300 feet of a drab, earthy, somewhat porous, lime- 
stone, sometimes inclosing small pebbles, underlaid by beds, which 
erade off insensibly from limy sandstones into coarse gravel beds. 
They occupy the valley ofthe North Platte to the South of Jack’s 
creek, forming long, gentle slopes, extending up from the river to the 
flanks of the Grand Encampment mountain, which, though so covered 
by recent deposits that only few exposures of the underlying Tertiary 
are found, sufficiently show the continuity of their original deposition. 
Their beds may be traced along the line of bluffs bordering the valley 
of Sage creek on the south and west. Here the upper member is a 
hard silicious shale, more like an older rock, under which are seen the 
white limy sandstones ; the lower beds being concealed beneath debris 
accumulations. 
Arnold Hague found the White River Group along the south and 
east face of Chalk bluffs, in Wyoming, resting unconformably upon 
the Laramie Group, and protruding from beneath the Pliocene beds. 
The strata are exposed near Carr’s station, on the Denver Pacific 
Railroad, eastward across Owl creek, the tributaries of Crow creek, and 
beyond. The thickness of the group is estimated at 300 feet, and is 
of Miocene age. 
