Emery — Green River Desert Section, Utah. 575 



found in profusion strewing- weathered surfaces, and also 

 contain toward the top bones of large dinosaurs. The 

 variegated shales are capped by a bed of coarse sandstone 

 or conglomerate which forms a prominent bench, and 

 above which is a series of coarse sandstones and con- 

 glomerates with small amounts of gray or pale-tinted 

 variegated shale. This part of the section is extremely 

 variable in lithology and color but is in general charac- 

 terized by a predominance of sandstone which, though 

 light on fresh surface, is somber gray or black in color 

 on the weathered face due to' desert varnish. The 

 accompanying stratigraphic section gives details of the 

 beds in the McElmo formation above the Salt Wash 

 member. 



Section of upper part of the McElmo formation three-fourths 



mile west of Jesse's Twist in the Greenriver- 



Hanksville road. 



(Measured by Milton Anderson.) 



1. Conglomerate, light-colored, massive, cross-bedded 15' 



2. Shale, light-colored, sandy, containing beds of gray- 



ish sandstone 75' 



3. Conglomerate, grayish in general color, but contain- 



ing well worn, red, blue, black quartz pebbles, 

 loosely cemented, makes a ledge 25' 



4. Shale, grayish purple, containing four thin beds of 



sandstone and capped by layer of white shale two 



feet thick 38' 



5. Sandstone, brownish gray in color, in beds 18" thick 



alternating with purple and gray shales 15' 



6. Sandstone, brownish gray, coarse-grained, irregu- 



larly bedded, ledge maker .< 20' 



7. Shale, variegated purple, graj^, red, containing well- 



polished pebbles resembling gastroliths, with local 



thin sandstone beds 170' 



Total 358' 



The beds just described and included by Gilbert 25 in 

 the "Flaming Gorge group," were referred to the 

 McElmo by Lupton, 26 who also placed in this formation 

 the underlying Navajo and Todilto. In the present 

 paper these two, formations have been referred to the 

 La Plata group of rocks (Jurassic) for reasons already 

 presented. The lower limit of the McElmo (Cretaceous?) 



25 Gilbert, G. K., op. cit. 



26 Lupton, C. T., op. cit. 



