RECONNAISSANCE IN COLORADO AND UTAH 657 
section, implying a stratigraphic break comparable to that we found, 
and the probable horizon of the break is below the conglomerate. 
The question as to the correlation of the Dolores formation 
with some portion of the Plateau section generally assigned to the 
Fic. 7.—Near head of Cafion Colorado, Utah. Shows massive Vermilion Cliff 
(Dolores) Triassic sandstone, thinner sandstones above, and, in knoll on left hand, 
the lowest sandstones of the La Plata Jurassic. 
Trias becomes mainly a study of what has been called the “‘Shinarump 
Group” by Powell and particularly of the relatively thin bed called 
the ‘“‘Shinarump conglomerate.” I have made such a study and 
