191S 1 Moody-Taliaferro: Anticlines Near Sunshine, Wyoming 449 



intrenched, cutting within the discordant beds continued without alter- 

 ation of direction of the stream course. The history of the larger 

 streams is undoubtedly more complex, but the main fact of' their 

 superposition from the "Wasatch appears to be identical with what has 

 happened more recently on Gooseberry Creek. 



STRATIGRAPHY 



Introduction. — The formations exposed at the surface within the 

 area mapped are all sedimentary rocks. In age they range from the 

 Lower Cretaceous to the Quaternary. Tertiary voleanics occur a few 

 miles to the south of the southern limit of the area. 



The succession of the formations, their age and characteristic 

 features are given in the following table : 



System or 

 Series 



Group 



Formation 



Thickness in 

 feet 



Charaeter 



Quaternary 









Alluvium along stream courses 











Terrace gravels along Wood and 

 Greybull Rivers, consisting of 

 volcanic, limestone, and 

 quartzite pebbles and boulders 



Tertiary 





Wasatch 

 formation 





Gray to red conglomerates and 

 sandstones, white to bright 

 red sandy clays, thin tuffa- 

 ceous layers 





Montana 



Mesaverde 

 formation 



1000± 



Tan, buff, and gray sandstones, 

 buff sandy shales, carbonace- 

 ous shales and coal beds 







Cody shale 



1800± 



Dark gray and black shales with 

 numerous calcareous and li- 

 monitic concretions, gray and 

 buff sandy shales and thin 

 sandstones 











Upper 

 Cretaceous 





Frontier 

 formation 



583 



White to brown sandstones and 

 sandy shales; ratio of sand- 

 stone to shale 7:5 





Colorado 



Mowry 

 shale 



380 



Hard blue black fissile shales 

 and dark gray sandy shales 

 with a few hard sandstone 

 layers. Fish scales, fins, and 

 teeth abundant 







Thermopolis 

 shale 



470 



Rather soft dark shales, thin 

 brown sandstones 



Lower 

 Cretaceous 





Cloverly 

 formation 



305+ 



Dakota (?) sandstone member 

 at top, 55 feet thick. Red, 

 gray, and buff clays and 

 sandy clays, gray to lilac 

 limestone and gray sandstones 



