PRELIMINARY CORRELATION OF TERTIARY DEFORMATION AND SEDIMENTATION IN BIGHORN BASIN 



Deposition or Er< 



Deposition or Erosion 



Upper 



Early basic 

 breccias 

 (widespread) 



Basic tuff ( ?) 

 (local) 



Erosion ( ?) 



Erosion ( ?) 



Upper 



Tertiary ( ? 



Erosion ( ?) 



-(Unconformity- 



(?)) 



"Early acid 

 breccia " 

 (local) 



(Conformity) - 

 Border Wa- 

 satch (local) 



Erosion 



(Unconformity) 



Normal faults 

 (local) 



— Heart - 



Mountain 

 overthrust , 



(Unconformity- 



(?)) 



Andesitic tuffs 

 (local) 



Normal faults 

 (local) 



— Heart 



Mountain 

 overthrust 



Erosion ( ?) 



— (?) 



Andesitic tutTs ( ?) 

 (local) 



Heart 

 -Mountain - 

 overthrust ■ 



Extensive nor- 

 mal faults 

 Large folds 

 Widespread 

 uplift 



(Conformity) — 

 Border Wa- 

 satch (local) 



Erosion 



(Unconformity) 



Local normal 

 faults 

 Small folds 

 Local uplift 



Tatman Mtn. 



beds 

 Lost Cabin beds 

 Lysite beds 

 Gray Bull beds 

 Sand Coulee 



beds 

 (Unconformity ( ?) ) - 



Local depres- 

 sion 



Depression 



Fort Union ( ?) 



(Local uncon- 

 formity) — 



Sinking ( ?) 



Widespread 

 sinking 



Clark Fork beds of Sinclair 



and Granger 

 Fort Union 



Widespread 

 sinking 



Local warping 



(Local uncon- 

 formity) 



Local warping 



-(?) 



(?) 



Lance formation 



(?) 



Sinking ( r 



Lance formation 



Sinking 



Lance formation 



1 the Tertiary (?) to conform witli the usage of the U.S. Geological Survey, although the local evidence indicates . 



