PALEOZOIC STRATIGRAPHY OF ROCKY MOUNTAINS 125 



pitted dolomite, probably representing part of Member 16. 19 feet, 



Labarge Mountain; 51 feet total, Teton River. 



Break in Sedimentation 



Main Division of the Jefferson Dolomite 

 (M.T., 681 feet, Labarge Mountain) 



14. Imperfectly exposed. Ledges of fine-grained, brown dolomite. Float 

 of thin-bedded, drab and buff dolomite also. M.T., 160 feet, Labarge 

 Mountain. 



13. Cliff-making, steel-gray or gray-brown, fine-grained, calcitic, pitted dolo- 

 mite. M.T., 65 feet, Blacksmith Fork. 



12. Very poorly exposed. Float of thin-bedded, light-gray and buff dolomite, 

 very calcitic, grayish -brown dolomite, and calcareous shale. M.T., 72 

 feet, Labarge Mountain. 

 8-1 1. Main body of the Jefferson dolomite in Wyoming and Montana. 

 Blackish to light-brown and brownish-gray, thick-bedded dolomite, 

 weathering to brown-gray or gray. Very fetid odor on fresh fracture. 

 Characteristically with a rough weathered surface. Locally calcitic, or 

 with some layers mottled and streaked with buff. Locally quite fossilifer- 

 ous at certain horizons. 312 feet, Logan; probably somewhat more at 

 Labarge Mountain and at Blacksmith Fork. 



10. (Differentiated at Antler Peak only.) Brown and drab to whitish dolomite 



with yellow-brown bands. M.T., 75 feet, Antler Peak. 

 9. Dark-brown, saccharoidal, fetid dolomite, with rough weathered surface. 

 M.T., 28 feet, Antler Peak. 



8B. White, drab, or pearl-gray dolomite, conspicuous because of its light color. 

 M.T., Labarge Mountain (Bed 16), 3 feet; Teton River (Bed 26), 1 foot 

 6 inches; Antler Peak (Bed 10), 3 feet; Crandall Creek (Bed 43), 2 feet 

 6 inches. 



8A. Light-brown to blackish-brown, fine-grained dolomite. M.T., 28 feet, 

 Antler Peak. 



6-7. Dense to finely crystalline, white, cream, or pale-gray dolomite, platy 

 to blocky. M.T., 37 feet, Teton River. In the Crandall Creek section 

 sedimentation appears to have recommenced with Member 7 after an 

 interval of nondeposition. 



5. Fine-grained or saccharoidal, dark-brown, fetid dolomite, with irregular, 

 pitted, weathered surfaces. M.T., 23 feet, Dead Indian Creek. 



4. White friable sandstone at Labarge Mountain, elsewhere represented, like 

 Member 15, by a bed of quartz grains more or less closely packed together 

 in a matrix of white or yellowish dolomite. M.T., 10 feet, Labarge 

 Mountain. 



Break in Sedimentation (?) 



