A 



V SWAN VALLEY 





Cp^ld 



Neeley Bojin 





Fig. 22.9. Cross sections of the northern central Rockies from the Caribou Range in Idaho east- 

 ward to the Hoback basin (north end of the Green River basin) in Wyoming. See section 2, Fig. 

 22.1. The sections are not continuous but each is staggered southward somewhat from west to 

 east. (Upper section adapted from R. Enyert's thesis; middle section adapted from K. Keenmon's 

 thesis; lower section adapted from Jack St. John's and Alex Ross' thesis, all of the University 

 of Michigan.) The Ferry Peak, Absaroka and Darby thrusts are Paleocene in age; the Cabin 

 thrust is late lower Eocene (post-Hoback fm.); and the Grizzly thrust is late middle Eocene 

 (post-Pass Peak congl.). Also a cross section from Hoback Range to the Gros Ventre Range across 



the Hoback basin, which is the north end of the Green River basin. Cf, Flathead quartzite; Cgv, 

 Gros Ventre formation; Cb, Boysen formation; Ob, Bighorn dolomite; Dd, Darby formation; Cbm 

 Brazer and Madison limestones; Ca, Amsden formation; Ct, Tensleep sandstone; Cw, Wells 

 (Amsden and Tensleep); Cp, Phosphoria fm; Id, Dinwoody and Woodside; Tic, Ankareh; Jn, 

 Nugget sandstone; Jtc, Gypsum Spring and Twin Creek; Js, Preuss and Stump; Kg, Gannett 

 group; Kbr, Bear River; Ka, Aspen; Th, Hoback fm.; Tp, Pass Peak congl.; Tc and Ted, Camp 

 Davis fm.; Tla, lower andesite, Tua, upper andesite, Ts, silt of Camp Davis; Kf, Frontier fm. 



